An appliance for controlling data transmission is described. The appliance includes a packet engine configured to acquire data regarding a flow of first data packets over a link and to determine transport communication protocol (TCP) characteristics for the flow. The appliance also includes a data transmission controller configured to receive second data packets, determine a rate of transmission based on the TCP characteristics, and determine, based on one or more criteria, whether to use a rate-based data transmission control to control a transmission of the second data packets. The data transmission controller is also configured to, responsive to determining that a rate-based data transmission control is to be used to control a transmission of the second data packets, cause the packet engine to transmit the second data packets in groups, wherein transmission times of each group of second data packets are determined based on the rate of transmission.

In a network environment, network congestion can occur when a link or a network node (e.g., a router) is overloaded with a large number of data packets, which can lead to significant transmission delay. Moreover, significant data packet loss can result, as the network node is unable to process the data packets and is forced to drop them. All these can lead to significant deterioration in network performance.
There are various schemes available to avoid overloading the network and to improve network performance. For example, transport communication protocol (TCP) provides a number of congestion control mechanisms, which include the use of a congestion window to control the amount of data sent into a network. A congestion window can define the maximum size of data that can be transmitted into the network within one network round trip time (RTT). RTT can be measured based on the time elapsed between when a sending device transmits a data packet and when the sending device receives, from the receiving device, an acknowledgment for the transmitted data packet. The congestion window can be increased to allow more data to be sent into the network, based on an indication that the network has capacity to transmit more data packets (e.g., a successful prior transmission of data packets through the network, which can be indicated by reception of acknowledgments that correspond to the transmitted data packets). The congestion window can also be decreased to allow less data to be sent into the network, based on an indication that that network is congested. Such an indication can be based on a detection of packet loss based on, for example, reception of certain number of duplicate acknowledgments, selective acknowledgments (SACK), when a timer that reflects an estimation of RTT expires before reception of acknowledgment, etc. The TCP congestion control mechanism also includes a retransmission algorithm, in which data packets are retransmitted when there is an indication that the data packets are lost. Moreover, TCP also allows delayed acknowledgment, in which several acknowledgments (in response to reception of several data packets) can be combined into a single acknowledgment, to reduce protocol overhead.
The aforementioned TCP congestion control mechanisms operate based on a number of assumptions. Such assumptions can include, for example: 1) the bandwidth of the bottleneck node (e.g., a router) remains the same; 2) changes in connection latency indicate packets being queued at the bottleneck node which indicates network congestion; 3) packet loss is typically an indication of, and is attributed to, network congestion; 4) packet reordering, which can also lead to duplicate acknowledgments, is a rare event and can be detected within a few packets; and 5) delayed acknowledgements are observed only when the delayed acknowledgement algorithm is active and are limited to one acknowledgement for a maximum of two packets.
Most, if not all, of the aforementioned assumptions can be inaccurate over some types of networks, such as a wireless network (e.g., WiFi, LTE, etc.). For example, in an LTE network, bandwidth can vary due to the channel/carrier aggregation techniques deployed at the lower layers. Also, there can be continuous latency variation, due to the retransmission mechanisms at media access control (MAC) and radio link control (RLC) layers. It has also been observed that at times of channel and carrier aggregation/de-aggregation, latency spikes to multitudes of the regular path latency. Moreover, high amounts of out-of-order packets, based on MAC and RLC configuration, may be observed. Furthermore, random data packet loss, which is not necessarily attributed to a network node's failure to process data packets due to congestion, occurs frequently in wireless network. Therefore, random data packet loss is typically not a reliable indicator of network congestion in such networks.
All these inaccurate assumptions can lead to incorrect determination of packet loss and/or incorrect determination of network congestion. For example, random data packet loss can be incorrectly interpreted to indicate network congestion. Also, under some wireless standards (e.g., 4G), a receiving device can send stretch acknowledgements, which can cover as much as a full RTT worth of data, but do not arrive within one RTT of the sending of the data. The delayed reception of stretch acknowledgments can affect the operation of TCP congestion control mechanisms in a number of ways. First, under TCP congestion control mechanisms, both the adjustment of the congestion window and the transmission of the next set of data packets are triggered by the reception of acknowledgments of previously-transmitted data packets, and can be postponed by the delayed reception of stretch acknowledgments that correspond to those previously-transmitted data packets, leading to underutilization of network resources. Second, in a case where an incorrect determination of congestion-related packet loss results when, for example, a stretch acknowledgment arrives later than the expected RTT due to the accumulation of data for the generation of the stretch acknowledgment, rather than due to network congestion, unnecessary reduction of congestion window size and retransmission of data packets can result. Network performance can deteriorate as a result.

System and method for rate-based packet transmission over a network


A mobile two-way communication antenna is mounted on a metal plate which is pivotally secured to a housing so as to pivot about a horizontal axis. An electric reversible motor drives an elongated screw which in turn moves a cam surface linearly. The cam surface coacts with the metal mounting plate for moving the plate and the antenna between a horizontal and a vertical position. Horizontally extending ground plane elements are provided in applications where the housing is nonconducting. These elements contact the metal mounting plate when the plate is in its full upright horizontal position.

The present invention is directed toward an antenna raising and lowering device and more particularly toward a device which is intended to be mounted on top of an emergency vehicle for remotely raising and lowering the two-way communication antenna thereof.
As a result of the additional equipment being added to emergency vehicles such as ambulances, fire engines, rescue squads and the like, the more modern vehicles are being made larger than older vehicles. This has created a serious problem with respect to two-way communication antennas which extend upwardly from the top of the vehicle. The problem results from the fact that while the vehicles are becoming larger, they continue to be garaged in existing firehouses and garages with existing door openings which, in many cases, have a height designed for the older and smaller vehicles. With only a small clearance between the top of the vehicle and the garage openings, antennas are frequently broken. This not only adds a significant expense but can seriously interrupt emergency aid while the two-way communication system is being repaired.
Numerous attempts have been made to provide a remotely controlled mobile antenna raising and lowering device. Most of these prior art devices, however, require substantial modifications to the vehicle in order to connect the device to the same. Other prior devices known to Applicant are intended to be mounted within the vehicle and therefore take up substantial space which could be put to other use.
U.S. Pat. No. 4,101,897 describes a collapsible mobile antenna system which is intended to be mounted on top of a vehicle. The system shown in this patent, however, is not motor driven but must be manually operated from outside the vehicle. Accordingly, this system could not be used while the vehicle is in motion.
The antenna raising and lowering device shown in U.S. Pat. No. 3,224,003 is motor driven. However, there is a direct interconnection between the motor and the antenna. As a result, if the antenna is in the down position and a defect in the motor system occurs, the antenna cannot be raised, thereby rendering the communication system inoperative. Furthermore, movement of the antenna is directly proportional to rotation of the motor which can result in very slow operation of the antenna.
In addition to all of the foregoing defects of the prior art known to applicant, applicant is not aware of any prior antenna raising and lowering devices which include a means for providing a ground plane for the antenna. Such a ground plane is very often necessary when the structure on which the antenna raising and lowering device is mounted does not provide an adequate natural ground plane.

Mobile antenna raising and lowering device


The invention discloses an electronics device for personal use, comprising at least a first main surface, and at least a first antenna for communication via electromagnetic waves between the device and a second party. The antenna is an array antenna comprising at least a first and a second antenna element, and is arranged on said first main surface. Suitably, the electronics device is a portable computer comprising a lid which may be opened or closed, said first main surface being the lid, so that the antenna is arranged in the lid of the portable computer.

There are a number of known wireless technologies which may be used for connecting electronics devices such as computers to, for example, a network or to each other. Examples of known such systems are 3G, WiMAX, and WLAN. Most such existing systems move toward higher and higher bit rates, and one way of achieving such an increased bit rate is to use so called MIMO technology (Multiple Input, Multiple Output).
One way of achieving MIMO is to use several antennas with outputs which are decorrelated with respect to each other (uncorrelated antennas). It is known to equip computers, especially portable computers ("laptop" computers), with several orthogonal and thus decorrelated antennas. However, known such antenna systems utilize the available surfaces on the computer in order to make the coupling between the antennas as small as possible by spacing them as widely apart as possible.
The area available on the computer is thus not used to efficiently increase the "link budget".

Multi beam repeater antenna for increased coverage


The data transmission rate (DTR) of a data devices (12) connected to a data transmission service is controlled to be within an authorized collective DTR for the data devices, such as the authorized total DTR for a customer. The data devices transfer data to and/or from a data storage system (20) through front end hosts (16). The front end hosts send messages to a controller (22A) reporting the amount of data transferred and the data devices responsible for the data transfer. The controller determines whether the data devices are exceeding the authorized collective DTR and, if so, directs the front end hosts to increase the latency or delay before a front end host acknowledges receipt of data from the data devices and/or to decrease the buffer size in the front end host with respect to those data devices. This brings the DTR within the authorized collective DTR.

An entity needing data transfers from numerous devices can become a customer of a data transmission (and storage) service and contract with the service to provide a specified data transmission rate for the customer's devices. If a device or devices of the customer send too much data too quickly the customer can be charged for the excess data transmission rate, or service to some of the customer's devices can be interrupted, generally without the customer having advance notice of the problem or being able to control which devices have interrupted service.
Selectively disconnecting devices when the authorized data transmission rate is exceeded is not desirable because of the network overhead typically involved with reconnecting a device. Further, instructing a device to change its data transmission rate is generally not possible because most devices do not have that capability. In addition, communicating instructions to the devices can be difficult because different devices often have different protocols. This can result in the customer buying a higher data transmission rate than normally needed just to prevent devices from being dropped from the network when the authorized data transmission rate is exceeded, or the customer taking a chance that an important device will not lose service at a critical time.
This can be expected to become a greater and greater problem in the future as the "Internet of Things" gains more usage, and more and more devices are connected to the Internet. The "Internet of Things" is a term generally referring to a myriad of different devices and types of devices being connected or interconnected via the Internet. The devices can range from having limited available resources (memory size, processor speed, etc.) and needing small or infrequent data transmissions to having substantial available resources and needing large and/or frequent data transmissions.

Controlling data transmission rates of multiple devices


A programmed digital computer control system determines the turbine steam flow changes required to satisfy the speed and load demand made on the operation of a large electric power stream turbine for which substantially constant throttle pressure steam is generated. Load control is directed to plant electric power generation and it is based on feedforward valve positioning operation with feedback multiplication calibration for plant load and/or turbine speed error. Changes in the turbine operating level are limited by dynamic constraints applied by the computer.

The present invention relates to elastic fluid turbines and more particularly to systems and methods for operating steam turbines and to electric power plants in which generators are operated by steam turbines.
One general type of steam is the extraction type which typically although not necessarily would be classed as a small turbine and which further would be typically designed to supply the extracted steam required for a plant process and the turbine motive flow required for driving an industrial plant or electric power plant generator of predetermined electric power rating. Thus, an extraction turbine of suitable design rating might act as a prime mover in operating a paper mill plant generator while simultaneously supplying steam flow extracted from the main turbine steam flow for the paper making process and other purposes. Operation as a prime mover may be either a primary or a secondary role of the extraction turbine. Other turbines similar in end function to the extraction type include (1) back pressure turbines which exhaust motive steam flow under pressure control for process, heating or other purposes and (2) seawater conversion turbines which operate electric power generators and supply the steam flow needed for heating the converted seawater in a desalination plant. Turbines employed in the latter application may be of the extraction or back pressure type.
Another general type of steam turbine is that in which the steam is used primarily only to operate the turbine as a prime mover in power plant and other applications. In large electric power generation plants, such turbines drive large electric generators and are therefore of relatively large size and capacity. Turbine configurations vary from power plant application to application, and, in a fossil fuel fired plant, a turbine typically might include high pressure, intermediate pressure and low pressure sections tandemly interconnected on a single or multiple shaft with one or more successive reheat stages between the sections. A preselected power plant steam generating system provides steam to operate the turbine primarily only to generate electric power, but the turbine may also perform some relatively low power auxiliary functions such as boiler feed pump operation. Other prime mover turbines include shipboard electric generation turbines and ship propulsion turbines which are operated to control propeller torque and ship speed.
The extraction and prime mover turbines are the principal turbine types which are defined by the partitioning of different kinds of steam turbines on the basis of the character of the use made of the turbine inlet steam. Partitioning can also be made on the basis of the character of the steam generating system, and fossil fuel turbines and nuclear turbines are the principal steam turbine types defined under this characterization.
At the present time, commercial nuclear turbines are principally used in electric power generation applications although they have been proposed for other nuclear applications such as sea water conversion plants. Nuclear turbines and their control systems generally differ according to the character of the nuclear steam generating system, i.e. the boiling water reactor system, the pressurized water reactor system, etc. Fossil fuel turbines and particularly their control systems normally also differ according to the type of steam generating system employed, i.e. the drum type boiler system, the once through boiler system, etc.
Each general type of turbine may also be subpartitioned into different subtypes on the basis of preselected turbine characteristics such as power rating, structural design, steam pressure and/or temperature design operating characteristics, number of turbine sections and stages, turbine steam flow arrangement, number of rotor shafts (i.e. presence or absence of compounding), number of reheat stages, etc. Typically, because of the region of steam table operation and other operating characteristics of reactor steam generating systems, nuclear turbines are designed to operate with dry saturated steam at a relatively low throttle pressure such as 800 psi whereas the high pressure section of a large fossil fuel electric power plant turbine would typically be designed to operate with highly superheated steam at a much higher throttle pressure such as 3500 psi.
With respect to steam turbine control, prime mover turbine controls usually operate to determine turbine rotor shaft speed, turbine load and/or turbine throttle pressure as end controlled system variables. In the case of large electric power plants where steam throttle pressure controlled by the steam generating system, turbine control is typically directed to the megawatt amount of electrical load and the frequency participation of the turbine after turbine rotor speed has been controllably brought to the synchronous value and the generator has been connected to the electric power system.
Among other types of control, propulsion turbine control typically determines the turbine shaft speed and torque as in the case of ship propulsion turbines. Extraction turbine controls are normally operated to determine turbine speed and/or load as well as extracted process steam pressure as end controlled system variables. Extraction turbine operation thus requires multivariable control system operation, i.e. the prime mover and the process steam requirements are integrated in the determination of control actions and operating strategies to be taken. Back pressure turbines and sea water conversion turbines also typically entail the use of specially functioning controls in their operation.
The end controlled plant or turbine system variable(s) and turbine operation are normally determined by controlled variation of the steam flow to one or more of the various stages of the particular type and the particular design of turbine in use. In prime mover turbine applications such as drum type boiler electric power plants where turbine throttle pressure is externally controlled by the boiler operation, the turbine inlet steam flow is an end controlled steam characteristic or an intermediately controlled system variable which controllably determines in turn the end controlled system variable(s), i.e. the turbine speed, the electrical load, or the turbine speed and the electrical load. It is noteworthy, however, that some supplemental or protective control may be placed on the end controlled variable by additional downstream steam flow control such as by control of reheat valving and to that extent inlet turbine steam flow control is not strictly wholly controllably determinative of the end controlled system variables under all operating conditions.
Among other turbine types which can operate with externally controlled throttle pressure, extraction turbines use inlet steam flow control to provide partial determination of the end controlled system variables, i.e. turbine speed and extraction pressure. Downstream steam flow control interacting with the inlet steam flow control provides the balance of the determinative control placed on the end controlled extraction turbine system variables.
Where independent external control does not wholly control turbine throttle pressure such as in boiling water reactor turbine plants or in once through boiler turbine plants, inlet turbine steam flow control may be used to regulate throttle pressure as an end controlled or constrained system variable. In that event, turbine steam flow control determines the end plant system variable(s) such as plant electrical load subject to the control or constraint of throttle pressure.
In determining turbine operation and the end controlled system variables, turbine steam flow control has generally been achieved by controlled operation of valves disposed in the steam flow path(s). To illustrate the nature of turbine valve control in general and to establish simultaneously some background for subsequent description, consideration will now be directed to the system structure and operation of a typical large electric power tandem steam turbine designed for use with a fossil fuel drum type boiler steam generating system.
Steam generated at controlled pressure may be admitted to the turbine steam chest through one or more throttle stop valves operated by the turbine control system. Governor or control valves are arranged to supply steam to steam inlets disposed about the periphery of the high pressure turbine section casing. The governor valves are also operated by the turbine control system to determine the flow of steam from the steam chest through the stationary nozzles or vanes and the rotor blading of the high pressure turbine section.
Usually, full arc admission governor valve operation with throttle valve control is employed during turbine startup primarily because excessive thermal rotor stress is caused by partial arc admission operation. At some point in the speed or load buildup dictated by efficiency and/or other considerations, the throttle valving is opened fully and steam flow control is transferred to partial arc governor valve operation.
Torque resulting from the work performed by steam expansion causes rotor shaft rotation and the reduced pressure steam is usually then directed to a reheat stage where its enthalpy is raised to a more efficient operating level. In the reheat stage, the high pressure section outlet steam is ordinarily directed to one or more reheaters associated with the primary steam generating system where heat energy is applied to the steam. In large electric power nuclear turbine plants, turbine reheat stages are usually not used and instead combined moisture separator-reheaters are employed between the tandem nuclear turbine sections.
Reheated steam crosses over to the next or intermediate pressure section of the large fossil fuel turbine where additional rotor torque is developed as the intermediate pressure steam expands and drives the intermediate pressure turbine blading. One or more interceptor and/or reheat stop valves are usually installed in the reheat steam flow path or paths in order to cut off or reduce the flow of turbine contained steam as required to protect against turbine overspeed. Reheat and/or interceptor valve operation at best produces late corrective turbine response and accordingly is normally not used as a primary determinant of turbine operation.
Additional reheat may be applied to the steam after it exits from the intermediate pressure section. In any event, steam would typically be at a pressure of about 1200 psi as it enters the next or low pressure turbine section usually provided in the large fossil fuel turbines. Additional rotor torque is accordingly developed and the vitiated steam then exhausts to a condenser.
In both the intermediate pressure and the low pressure sections, no direct steam flow control is normally applied as already suggested. Instead, steam conditions at these furbine locations are normally determined by the mechanical system design subject to time delayed effects following control placed on the high pressure section steam admission conditions.
In the typical large fossil fuel turbine just described, thirty percent of the total steady state torque might be generated by the high pressure section and seventy percent might be generated by the intermediate pressure and low pressure sections. In practice, the mechanical design of the turbine system defines the number of turbine sections and their respective torque ratings as well as other structural characteristics such as the disposition of the sections on one or more shafts, the number of reheat stages, the blading and vane design, the number and form of turbine stages and the steam flow paths in the sections, etc.
A variety of valve arrangements may be used for steam control in the various turbine types and designs, and hydraulically operated valve devices have generally been used for steam control in the various valving arrangements. The use of hydraulically operated valves has been predicated largely on their relatively low cost coupled with their ability to meet stroke operating power and positioning speed and accuracy requirements.
Previous automatic turbine control schemes involving hydraulic turbine valves were based on principally hydraulic feedback control having some mechanical couplings as shown for example in prior art extraction turbine control U.S. Pat. Nos. Bryant 2,552,401 and Marsland 1,777,470 or principally mechanical feedback control as exemplified in prior art U.S. Pat. No. Eggenberger 3,027,137. Thereafter, advances in electronic solid state circuitry with its inherent reliability made it desirable to employ electrical feedback principles for automatic hydraulic valve control in commercial applications. Electrohydraulic analog type turbine control systems are described in prior art U.S. Pat. Nos. including for example Bryant 2,262,560, Herwald 2,512,154, Eggenberger 3,097,488; 3,097,489; 3,098,176 and Callan 3,097,490.
An early solid state electrohydraulic analog-digital turbine control system known as DACA has been applied in a number of customer installations by Westinghouse Electric Corporation. The DACA system relates primarily to turbine speed control in various applications such as paper mills and ships. Extraction type analog turbine control systems also have employed electrohydraulic control as set forth for example in prior art U.S. Pat. Nos. including Wagner 2,977,768, 3,064,435, 3,091,933, 3,233,412 and 3,233,413.
Generally, prior art analog or analog-digital electrohydraulic turbine control systems employed closed loop feedback operation. Basically, the end system variable controlled by valve operation or a representation of that variable may be sensed and compared to a setpoint value to generate an error signal. Circuitry including an analog controller acts on the error signal with preset loop gain and often with a preset transfer characterization to develop a control signal which effects hydraulic operation of the turbine steam valving through a valve positioning control including a servo valve, an actuator, and a position error feedback driven controller which operates the servo valve. When the error is reduced to zero, corrective valve control action is terminated.
In prime mover turbines, a speed error signal may determine the control action alone or in conjunction with a load control signal. As another prior art turbine control loop example, multivariable extraction turbine control action requires separate speed and extraction pressure control loops with the speed and pressure error signals directly determining the speed and pressure loop control actions respectively and with crossover coupling between the loops modifying the pressure and speed loop control actions respectively.
When the end variable controlled by valve operation is turbine load as in large constant throttle pressure electric power plant turbines, the load control loop may be open or closed and it usually operates jointly with the closed speed feedback loop. After the turbine is brought to synchronous speed by speed loop operation, the speed error normally holds at zero and the load control loop operates the steam valving to determine the turbine steam flow and the amount of the total system load shared by the turbine. To hold synchronous speed, frequency participative speed control action is applied during transient speed disturbances caused by large load changes.
In some prior art cases, the load control loop may be open or substantially open in operation in that valve positions are instituted manually or automatically to provide desired or reference load, and subsequently valve setting changes are manually initiated if the generated megawatt reading or other load detecting variable is in error. Faster but still delayed load control is achieved in other art cases with the use of an interstage reheat pressure signal as a closed load loop feedback signal. The fastest load control has been obtainable with the use of impulse chamber or first expansion stage closed loop pressure feedback.
In this as well as the general prior art case, suitable characterizing circuitry may be included in the load control loop in operating upon the load demand, i.e. the load reference or the load error signal. Typically, the characterization may statically compensate for the usual nonlinear valve position-flow characteristics thereby producing a linear relationship between controlled steam flow changes and changes in the load demand level or it may introduce nonlinearity intended to produce valve back seating.
A commercially supplied prior art electrohydraulic turbine control scheme is shown and described more specifically in a printed paper entitled "Electrohydraulic Control For Improved Availability and Operation of Large Steam Turbines" and presented by M. Birnbaum and E. G. Noyes to the ASME-IEEE National Power Conference at Albany, N.Y. during Sept. 19-23, 1965. In that scheme, feedback control is employed to regulate turbine speed and load in large electric utility steam turbines. Some digital circuitry is included especially a solid state digital reference system which eliminated earlier speed/load changer motor systems for establishing the turbine speed and load setpoint changes on a permissive ramp scheduled basis. An article entitled "Automatic Electronic Control Of Steam Turbines According To A Fixed Programme" in the March 1964 issue of the Brown Boveri Review relates to similar subject matter.
Although the known various types of prior art electrohydraulic turbine control and electric power plant systems have in general provided satisfactory turbine and power plant operation and control results, they have had particular shortcomings many of which are inherent consequences of the basic character of these systems. For instance, as already indicated, it has been the practice to utilize feedback operated loops or uncorrected open loops in which transfer function circuitry provides compensation for nonlinearity in the position-steam flow characteristic curves of the turbine valves and there are inherent in this feature certain disadvantages.
The purpose of using the static compensation characterizing circuitry is to attempt to make the steam flow rather than the steam valve position proportional to the feedback error demand or the reference demand and thereby make the amount of control action proportional to the amount of demand placed on the control. It is inconvenient and often difficult to realize accurately linearizing transfer function circuitry for the variously characterized valves with which a control would be associated in any particular turbine unit or from turbine unit tc turbine unit of production. One reason for this is that each valve or valve arrangement might require a special accurately linearizing transfer function and accordingly necessitate special and relatively costly electronic hardware to obtain that function.
Another and perhaps more significant reason is that a truly linearizing transfer function circuit may not be economically and feasibly obtainable such as where the valve position-flow characteristic in general has a positive slope but along one or more curved segments it has negative sloping with zero slope turning points at each of the segment ends. Further, even where appropriate linearizing transfer function circuitry is developed for a particular valve arrangement, system usage can change the valve position-flow characteristic as a result of valve wear, etc. and the original inflexible static transfer function circuit no longer accurately achieves its purpose thereby inconveniently making maintenance modification desirable or necessary.
In the general case, it is noteworthy by extension that the same or similar comments apply regarding applications difficulties where static control system transfer functions selected before or during turbine operation are used to produce some relationship either linear or other than linear between the controlled steam condition such as flow and the demand made on the control system. Because of the related shortcomings in control loop static characterization, prior art turbine operation and control have been deficient across the turbine art from the standpoint of efficiency and accuracy. In the area of electric power plant turbines supplied by fossil fuel fired drum type boilers or other steam generating systems, inefficiencies and inaccuracies stemming from these shortcomings have caused reduced power generating control flexibility and higher generating costs.
Apart from static characterizing, another difficulty with prior electrohydraulic turbine valve control systems and associated turbine operation has been the limited utility experienced with respect to turbine dynamics, i.e. controlling the speed of steam valve response and the speed of turbine energization response. Typically, turbine control systems have control looping which is dynamically characterized with proportional action and with appropriate gain for stable valve positioning and stable turbine drive responses. A loop so characterized may or may not result in desired dynamic steam valve response and desired dynamic turbine steam energization response and, in electric power plants, desired power generation response as the system operating conditions undergo variation.
One aspect of the dynamic characterization difficulty stems from the fact that different magnitudes of change in the valve position setpoint may require different positioning loop gains in order to achieve the desired dynamic valve positioning response on a consistent basis. For example, it may be desired to produce fast stable valve positioning operation with huntless 10% overshoot. A small position setpoint change may require a first gain G.sub.1 to achieve this response while a larger position setpoint change may require a second and higher gain G.sub.2. Since the positioning gain is typically fixed, the desired valve positioning response can only be achieved within a limited range of valve position setpoint changes.
Further difficulty has been experienced with conventional turbine control dynamic characterization from the standpoint of control loop bandwidth limitations on the amount of loop gain usable for achieving stable response. This limiting and inefficient quality of the prior art requires relatively reduced loop gain to limit noise interferences with control action. Thus, a limit is placed on the speed with which valve position and turbine steam energization responses can be achieved where a faster response might otherwise be desirable and obtainable within the limits of turbine thermal and mechanical dynamics. Bandwidth limitations on turbine process control capability especially arise in turbine control systems having cascaded loops with summing junctions, such as in large electric power plant turbine control systems where the gain of an inner valve positioning loop acts on the output of an outer load control loop and thereby requires a cutback in outer loop gain to achieve adequately low response level to outer load control loop noise signals.
Another aspect of the dynamic characterization difficulty stems from the fact that a typical proportional action loop, even though it may act in some circumstances with the desired fast and accurate valve positioning within the limits of turbine thermal and mechanical capabilities, will in most cases cause overdamped turbine steam energization response because a changed steam flow requires time to cause the steady state steam drive energization of the turbine to reach the new level corresponding to the new steam flow. The significance of this shortcoming varies in accordance with the amount and the significance of the excessive time delay involved in the turbine energization response. In the case of large electric power turbines, the difference in time between critical and typically overdamped responses is relatively short in comparison with other plant operating limitations and therefore has not been too objectionable. In other words, electric power plant turbine energization response normally is nonoptimal in the strictest sense, yet little or no power plant operating advantage is normally obtained by increasing the speed of turbine energization response because of other plant constraints. However, in at least some possible electric power plant applications and in other turbine applications across the turbine art where optimal or more nearly optimal turbine dynamics have been desirable or would be desirable if practically achievable, previous turbine controls have been somewhat deficient.
To produce some increase in turbine response speed, prior controls might use some dynamic characterization including analog rate action for example. In that event, steam valve positioning may be produced within the limits of turbine thermal and mechanical dynamics with valve position overdrive which persists beyond the previously noted quickly executed 10% overshoot used for achieving fast nonhunting valve positioning. As a result, steam flow temporarily overshoots, and faster nonovershoot turbine drive energization is produced as valve position is ultimately countercorrected to provide the required steady state steam flow. However, as in the case of static characterization, the dynamic characterization cannot be adjusted conveniently to provide stable and consistently faster turbine response under varying operating conditions.
Prior art difficulty in the area of dynamic characterization and its role in determining steam valve response and turbine energization response and, in electric power plants, power generation response thus stems from inability to achieve particular responses as well as from relatively rigid inability to achieve (1) conveniently selectable response after system installation and before system operation and (2) convenient or automatic variation in steam valve response and turbine energization response needed after system startup to meet particular performance specifications under different operating conditions or to satisfy the requirements of optimizing or near optimizing control. Operating and control efficiency and accuracy have thus been adversely affected in the area of electric power plant turbines as well as across the entire turbine art by inflexibility of control loop dynamic characterization.
As in the case of static characterization and other prior art deficiencies, slowness of turbine control and inaccuracy and inefficiency of turbine operation resulting from inadequate prior art dynamic characterization have led to objectionable deviation of the end controlled system variable(s) from the desired value(s). For example, steam turbine slowness in driving an electric power plant generator accurately to a new power contribution level can negate some of the economic gain otherwise achieved by the functioning of an economic dispatch computer.
In addition to relatively costly hardware changes required for changed static characterizing transfer functions from unit to unit of a particular type of turbine, there have been long standing, costly and inflexible differences in hardware design among the conventional control systems tailored for the various types of turbines, i.e. extraction turbines, large electric plant turbines, boiling water reactor turbines, pressurized water reactor turbines, etc. Although different specific turbine operating characteristics and control results are necessary for the various turbine types, the capital costs associated with the wide variety of prior art turbine control hardware needed for this purpose have, certainly along with other factors, generally inhibited the marketability of steam turbines and steam turbine controls.
The relatively high capital cost characteristic of conventional inflexible turbine controls has also in general limited the extent to which functional sophistication can be incorporated in turbine operation, i.e. more advanced functioning requires increasingly more costly hardware application. Inflexibility and high cost of conventional turbine controls has more specifically restrictively affected development of integrating controls for large system applications which include steam turbines as a large component piece of equipment. Thus, the special engineering needed for interfacing prior art turbine controls with plant associated controls, such as steam generating system controls in an electric utility plant, has for economic and other reasons limited the advanceability of the turbine operation and control art by limiting the extent to which the interfacing can be made more integrational or more interdependent.
In a similar manner, inflexibility of conventional large turbine control schemes has even caused the capital cost of state of the art hardware systems to become objectionable. Thus, interlock and supervisory circuitry and equipment required for system monitoring, supervision, protection and sequencing has in many cases expanded to comprise as much as eighty percent of the control system hardware cost. The inconvenience and cost of modifying the wired hardware after installation to achieve needed changes in interlock, supervisory and like functions has resulted in further difficulty and objection.
In brief summary, it is clear that prior art operation and control of the various types of steam turbines including large electric power steam turbines are characterized with (1) inaccuracy and inefficiency in steam turbine operation and electric power plant operation due to limited steam valve operating accuracy and limited and inflexible control loop static characterization, (2) inaccuracy, inefficiency and slowness in steam turbine and electric power plant operation due to limited steam valve control flexibility and limited control loop dynamic characterization, (3) inaccuracy and inefficiency in the operation of electric power and other cascade loop controlled steam turbines and in electric power plant operation due to bandwidth limited control system response speed, (4) limited steam turbine and turbine control marketability caused by relatively high cost electrical control systems in turn caused generally by special hardware requirements such as extensive interlocking and supervisory hardware differences from system to system, and (5) limited steam turbine and turbine control marketability caused by the relatively high hardware cost associated with advancement of the art.
The state of the turbine operation and control art is improved and advanced by the present invention since it is arranged and organized to provide improved turbine performance with reduced relative cost. It achieves these results in its preferred form with the employment of a programmed digital computer.

System and method for operating a steam turbine and an electric power generating plant


A spinning machine is disclosed which includes a sliver feeding device for introducing sliver into a spinning unit from a sliver container. To accommodate picking out the starting portion of a new sliver from a container and for connecting it with an end portion of the old sliver entering the spinning unit, apparatus is provided for picking up the new sliver and supporting the same in such a manner that the old sliver and the new sliver overlap one another in the area of the sliver supporting device adjacent the inlet area of the feeding device of the spinning unit.

The invention relates to a spinning machine having a plurality of adjacently arranged spinning units, each containing a sliver feeding device for the withdrawal of a sliver from a container and for the introduction of the sliver into the respective spinning unit, and having devices for picking up the starting portion of a new sliver of a readied container and for connecting it with the end portion of the old sliver entering into the spinning unit.
In the case of a known spinning machine of the initially mentioned type (DE-A 35 01 875 corresponding U.S. Pat. No. 4,653,26), it is provided that either the connecting of the end portion of the old sliver with the starting portion of the new sliver takes place such that approximately the same number of fibers exist in the connecting point, or that, before a piecing, the sliver feeding device first remains switched on until the connection point between the slivers has entered into the spinning unit, the fibers which are fed to the spinning point not being used for the spinning process but being removed as waste.
It is also known (DD-PS 107 952) to feed the sliver to a fine-spinning machine in large containers which, at the fine-spinning machine, are transferred to smaller containers circulating on a conveying device. The sliver will then enter into the spinning units from the smaller containers. Two of these smaller containers, so-called spinning cans, are assigned to each spinning unit, these spinning cans being arranged above one another. The end portion of the sliver of the just-serviced spinning can is connected with the starting portion of the sliver of the spinning can which is located in the supply position or of the new spinning can which is brought into the supply position, so that a continuous feeding of the sliver is possible.
It is also known (DE-C 26 46 313) to first completely use up the sliver in the respective spinning units and, as a result, generate a signal by means of which a supply of a container with a new sliver is triggered and possibly an automatic threading of the starting portion of the new sliver into the respective spinning unit.
An object of the invention is to further improve a spinning machine of the initially mentioned type by facilitating the connecting of the old and the new sliver.
This object is achieved in that each spinning unit, in an inlet area, is equipped with devices for supporting the entering sliver, and in that the devices for picking-up the starting portion of the new sliver can be applied to the devices for the supporting in such a manner that the old sliver and the new sliver overlap one another in this area of support.
This development provides the possibility that the slivers to be connected with one another can be pressed against one another, while they are located in a certain, specified position. This facilitates the connecting of the sliver sections.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Sliver splicing arrangement for a spinning machine


This invention relates to a starch based adhesive comprising a lyophilic colloid, a partially gelatinized starch and water and to a process for manufacturing such adhesives comprising the steps of mixing a lyophilic colloid with a starch and water and then partially gelatinizing the starch. Preferred lyophilic colloids include carboxymethyl cellulose and fully gelatinized starch. An advantage of the adhesive is that properties of the adhesive may be conveniently controlled by control of the ratio of the components and the degree of partial gelatinization.

Starch consists of microscopic granules which swell in hot water or in cold or warm caustic solution. The granules do not swell in cold water or in very dilute caustic solution. Onset of swelling commences if temperature is increased beyond a critical point or caustic addition exceeds a critical concentration. This process is known as gelatinisation. The changes in the starch granules during gelatinisation are observable and progressive. Initially, there is a slight swelling of the granules and a loss of birefringence. A gradual observable increase in viscosity follows accompanied by further granular swelling until a plateau is reached. Only after the plateau stage do the granules become fully swollen to their maximum size. If the swelling process is not arrested, the granules continue to swell until they burst. The viscosity increases sharply followed sequentially by the folding of the granules and the appearance of exudate. After the exudate appears, the starch is no longer granular in form but is a stringy mass at which stage the starch is said to be fully or completely gelatinised. If the swelling is arrested in the plateau prior to maximum swelling or bursting of the granules, the starch is said to be partially gelatinised.
Starch based adhesives have been used for the manufacture of corrugated boards since the early 1930's. Basically the preparation processes fall into two groups:
(a) The CARRIER SYSTEMS, where the bulk of the adhesive is raw starch (approximately 80-85%) and the desired viscosity of the adhesive is derived from a proportion (approximately 15-20%) of the total raw starch, this proportion acting as a carrier after being fully gelatinised through heating and/or through treatment with strong alkali solution. The balance of the adhesive remains non-gelatinised starch. Various other lyophilic colloids have been used in place of fully gelatinised starch as a carrier. The liquid phase of such adhesives consequently is relatively viscous.
(b) The NO-CARRIER or CARRIER-FREE SYSTEMS are described in Australian specifications Nos. 290,991, 425,716 and 432,257, where the desired viscosity of the adhesive is obtained by swelling the starch granules in the adhesive by gentle alkali and/or heat treatment so that all of the starch is partly gelatinised. The liquid phase of such adhesives is very thin as, according to the respective patents, a negligible proportion of starch is fully gelatinised, i.e. in the form of lyophilic colloid.
During the last few years there has been a change in the concept of producing corrugated boards. This probably has been brought about by rapidly escalating heat-energy costs and the looming shortage of oil.
The generally tightening economic conditions and the consequent demands for higher production rates has resulted in innovation both in application techniques and in equipment design.
The current requirement is for production of corrugated board with the minimum evaporation of water from the glue-lines. This would have advantages not only in terms of savings in heat-energy consumption, but also in terms of better warp-control of combined boards.
Adhesive application equipment has been improved to enable uniform metering of adhesive at very low film thicknesses and it is now possible to apply less than half of the film thicknesses commonly used. To complement the better application equipment, hot-plate sections have been shortened and more adequately temperature-controlled. However, existing starch-based adhesive systems do not satisfy all the requirements of a modern corrugating plant where application of low film thicknesses of adhesive is highly desirable.
The necessity for an adhesive not only to have the correct rheological properties but also the correct water holding capacity for an individual machine is becoming more and more important. It is therefore desirable to have an adhesive preparation system that allows these important properties to be conveniently varied to enable "tailor-making" adhesives not only for each individual plant, but also for the different units within a plant.


This invention relates to a magnetic recording medium comprising a non-magnetic support and magnetic layer provided thereon containing a ferromagnetic metal powder, the magnetic layer having a multilyaer structure consisting of a lower layer containing acicular grains obtained by dry process reduction and an upper layer containing chain-like grains obtained by wet process reduction, the upper layer being provided on the lower layer. This magnetic recording medium is particularly suitable for high density recording.

1. Field of the Invention
This invention relates to a magnetic recording medium and more particularly, it is concerned with a magnetic recording medium suitable for high density recording.
2. Description of the Prior Art
Ferromagnetic powders which have hitherto been used for magnetic recording media are maghemite, cobalt-doped maghemite, magnetite, cobalt-magnetite Berthollide compounds of maghemite and magnetite, cobalt-doped Berthollide compounds of maghemite and magnetite and chromium dioxide. However, these oxide-type ferromagnetic powders are not so suitable for magnetic recording of a signal of short recording wavelength (about 2 .mu.m or less) or for magnetic recording with a narrow track width (about 100 .mu.m or less) because their magnetic properties such as coercive force (Hc) and residual magnetic flux density (Br) are insufficient for high density recording.
Development of ferromagnetic powders having properties suitable for high density recording has lately been carried out vigorously and one of these material is a ferromagnetic metal powder.
The following methods are known as a method of preparing such a ferromagnetic metal powder:
(1) A method comprising heat-decomposing an organic acid salt of a ferromagnetic metal and reducing with a reducing gas, which is described in, for example, Japanese Patent Publication Nos. 11412/1961, 22230/1961, 14809/1963, 3807/1964, 8026/1965, 8027/1965, 15167/1965, 16899/1965, (U.S. Pat. No. 3,186,829), 12096/1966, 14818/1966 (U.S. Pat. No. 3,190,748), 24032/1967, 3221/1968, 22394/1968, 29268/1968, 4471/1969, 27942/1969, 38755/1971, 4286/1971, 38417/1972, 41158/1972, 29280/1973 and Japanese Patent Application (OPI) No. 38523/1972.
(2) A method comprising reducing an acicular iron oxyhydride, acicular iron oxyhydride containing another metal or acicular iron oxide derived from these oxyhydrides, which is described in, for example, Japanese Patent Publication Nos. 3862/1960, 11520/1962, 20335/1964, 20939/1964, 24833/1971, 29706/1971, 30477/1972 (U.S. Pat. No. 3,598,568), 39477/1972, 24952/1973, 7313/1974, Japanese Patent Application (OPI) Nos. 5057/1971 (U.S. Pat. No. 3,634,063), 7153/1971, 38525/1972, 79153/1973, 82395/1973, 97738/1974, U.S. Pat. Nos. 3,607,219, 3,607,220 and 3,702,270.
(3) A method comprising evaporating a ferromagnetic metal in a low pressure inert gas, which is described in, for example, Japanese Patent Publication Nos. 25620/1971, 4131/1972, 27718/1972, Japanese Patent Application (OPI) Nos. 25662-25665/1973, 31166/1973, 55400/1973, 81092/1973, Japanese Patent Publication Nos. 15320/1974 and 18160/1974.
(4) A method comprising heat-decomposing a metal carbonyl, which is described in, for example, Japanese Patent Publication Nos. 1004/1964, 3415/1965, 16868/1970, 26799/1974, U.S. Pat. Nos. 2,983,997, 3,172,776, 3,200,007 and 3,228,882.
(5) A method comprising electrodepositing a ferromagnetic metal powder using a mercury cathode and then separating the metal powder from mercury, which is described in, for example, Japanese Patent Publication Nos. 12910/1960, 3860/1961, 5513/1961, 787/1964, 15525/1964, 8123/1965, 9605/1965 (U.S. Pat. No. 3,198,717), 19661/1970 (U.S. Pat. No. 3,156,650) and U.S. Pat. No. 3,262,812.
(6) A method comprising reducing a solution containing a ferromagnetic metal salt with a reducing agent, which is described in, for example, Japanese Patent Publication Nos. 20520/1963, 26555/1963, 20116/1968, 9369/1970, 14934/1970, 7820/1972, 16052/1972, 41718/1972, 41719/1972 (U.S. Pat. No. 3,607,218), Japanese Patent Application (OPI) Nos. 1353/1972 (U.S. Pat. No. 3,756,866), 1363/1972, 42252/1972, 42253/1972, 44194/1973, 79754/1973, 82396/1973, U.S. Pat. Nos. 3,206,338, 3,494,760, 3,535,104, 3,567,525, 3,661,556, 3,663,318, 3,669,643, 3,672,867, 3,726,664, Japanese Patent Application Nos. 91498/1973, 92720/1973, 106901/1974 and 134467/1974.
In these methods for the production of ferromagnetic metal powders, the ferromagnetic metal powders obtained by reducing in a reducing gaseous stream as in the case of (1) or (2) have an acicular grain form and a grain size of 200 to 1000 A in short length axial ratio being within a range of 3 to 20, which are suitable for use as a magnetic recording medium. There are formed sometimes pores in the grains depending on the feature of the production method. Ferromagnetic metal powders are readily be obtained having a coercive force (which will hereinafter be referred to as "Hc") of 400 to 1500 Oe and a saturated magnetization (which will hereinafter be referred to as ".sigma.s") of 100 to 180 emu/g. In the above described methods (3), (4), (5) and (6), ferromagnetic metal powders are obtained in such a manner that globular or granular grains are arranged at a constant interval with some orientation or contacted with each other because a magnetic field is applied to the ferromagnetic powder during the production thereof, and sometimes these grains are orientated in an irregular state. In any case, these grains are chained like a necklace, which are called "chain grains", and those having magnetic properties such as Hc of 300 to 2000 Oe and .sigma.s of 70 to 140 emu/g are readily obtainable. As a grain size, a grain diameter of 150 to 800 A and grain length of 500 to 10000 A are desirable for magnetic recording media.
Magnetic recording media using the above described acicular grains alone have the following disadvantages:
(1) The squareness ratio (Br/Bm, hereinafter referred to as "SQ") is low and it is difficult to obtain a practical squareness ratio, i.e., 0.75 or more. Therefore, the self-demagnetization is large and a high sensitivity (5 MHz VS) cannot be obtained in spite of a large Bm (maximum magnetic flux density).
(2) The dispersibility with binders and the surface smoothness of a tape prepared using these grains are so bad that there are much noise and a low S/N (signal/noise) ratio.
(3) Head abrasiveness is large.
On the other hand, magnetic recording media using the above described chain grains alone have the following disadvantages:
(1) The saturated magnetization is smaller than when using the acicular grains.
(2) The apparent density is small and handling of the grains is hard. Therefore, a tape prepared using the chain grains should be subjected to supercalendering treatment because of its soft surface.
(3) The cost for the production thereof is higher than when using the acicular grains.
(4) The durability to contact with heads is shorter.
Various studies or efforts have hitherto been made on both the grains in order to solve the above described problems, but these problems have not been solved completely, which hinder practical use of these grains.
We, the inventors, have made efforts to provide a magnetic recording medium free from the above described disadvantages and consequently have reached the present invention, in particular, getting a hint from the prior art magnetic recording media having two or more different layers as magnetic layers.
Magnetic recording media having a multi-layer structure, for example, consisting of a .gamma.-Fe.sub.2 O.sub.3 layer coated on a Fe.sub.3 O.sub.4 powder layer are well known whereby the disadvantages of Fe.sub.3 O.sub.4, i.e., oxidation in air or poor reprinting property can be solved with keeping the high magnetic flux density of Fe.sub.3 O.sub.4. It is also known that the disadvantage of CrO.sub.2, i.e., head abrasiveness can be improved by the provision of a multilayer structure consisting of a CrO.sub.2 type magnetic layer and iron oxide magnetic layer coated thereon and that the sensitivity can be increased and the harmonic distortion factor and S/N property can be improved by the provision of a multilayer layer consisting of a plurality of layers differing in coercive force.
These known facts are disclosed in, for example, Utility Model Publication No. 18135/1959, Japanese Patent Publication Nos. 2218/1962, 8106/1964, 23678/1964, 5351/1965, 185/1968, 28681/1973, Japanese Patent Application (OPI) Nos. 18508/1972, 37903/1972, 31907/1973, 39995/1973, 81093/1973, 98803/1973, 55304/1974 and U.S. Pat. Nos. 2,643,130, 2,647,954, 2,691,072, 2,941,901, 3,052,567, 3,185,775, 3,328,195, 3,416,949, 3,676,217 and 3,761,311.


An uncomplicated, compact and environmentally-immune sensor for the degree f articulation of finger joints in a remote underwater vehicle uses a length of an optical fiber connected to each finger joint. As the joint is rotated, the bending of the optical fiber changes the attenuation of light through the fibers and a detector monitoring this change provides a signal that is correlated to the degree of articulation.

Devices for sensing a degree of rotation for angular disposition are critically important in remotely located mechanisms where a visual monitoring cannot be made. The need for accurate angular measuring devices particularly is felt in the broadening and the highly sophisticated field of robotics where precision unattended and unmonitored mechanical functions are to be flawlessly coordinated.
Hand-like manipulators having a number of interdependent articulated sections pose a still more formidable problem since most conventional potentiometer angular sensors are bulky and are susceptible to damage. The potentiometer sensors have shown a somewhat acceptable degree of resolution by providing indications of changed resistance, or voltage, but they are vulnerable to failure particularly when the manipulator or articulated joint is to be used in marine applications, most notably high pressure applications. When a number of potentiometer angular sensors are located in a small volume (on all the joints of a hand-like manipulator), an objectionable bulk is created. In addition, the group of potentiometer sensors cannot be operated without special precautions for underwater or adverse environments that can effect its resistance or the supplied electricity.
Thus, there is a continuing need in the state-of-the-art for an angular position indicator that is compact and reliable under adverse conditions to allow its use in an undersea manipulator or articulated joint to provide accurate angular position readings.

The United States of America as represented by the Secretary of the Navy


The present invention relates to a polymer resulting from the copolymerization of at least three monomers. From about 40 to 84 weight percent of the polymer is derived from a conjugated diolefin, from about 15 to 50 weight percent of the polymer is derived from a vinyl substituted aromatic compound and from about 1 to 8 weight percent of the polymer is derived from an olefinically unsaturated nitrile. These polymers may be added to a tread rubber stock for improved wet traction and improved abrasion resistance.

It is generally desirable to improve the wet traction of a tire tread. For example, it is common to compound high styrene SBR polymers in tread stock recipes with a concomitant improvement in wet traction. Unfortunately, along with the improvement in the wet traction there is a corresponding decrease in the abrasion resistance of the tire resulting in increased tire wear. For these reasons, it is very desirable to improve the wet traction of the tire without sacrificing the abrasion resistance.

Polymers derived from a conjugated diolefin, a vinyl-substituted aromatic compound, and olefinically unsaturated nitrile


The invention provides a novel additive for improved analysis by mass spectrometry. More specifically, ascorbic acid has been found to reduce or eliminate the presence of adducts commonly present in mass spectra. The improved processes and compositions of the invention allow for increased accuracy, sensitivity and throughput for samples analyzed by mass spectrometry.

Mass spectrometry is a powerful analytical tool used for measuring the molecular mass of analytes in a sample. When using a time-of-flight mass spectrometer, the speed of flight of the ions is about 107 times faster than the speed of migration of molecules in an electrophoretic gel, therefore mass spectrometry offers an extremely fast analytical method, even when measurement of the spectrum is repeated 10 to 100 times to achieve a good signal-to-noise ratio.
Analysis by mass spectrometry typically begins with the samples being ionized by any number of means, for example, by Matrix Assisted Laser Desorption Ionization (MALDI) or Electrospray Ionization (ES). MALDI preparation and measurement procedures consist first of embedding the analyte molecules on a sample carrier in a solid, IR or UV-absorbent matrix which is usually an organic acid. The sample carrier comprising the matrix and analyte is placed in the ion source of a mass spectrometer. The matrix is vaporized by a short laser pulse and the analyte molecule is thereby transported into the gas phase in a non-fragmented state. The analyte molecule is ionized by colliding and reacting with the matrix ions generated at the same time. A voltage is applied which accelerates the ions into a field-free flight tube. Due to their different masses, the ions in the ion source are accelerated to different speeds with the smaller ions reaching the detector earlier than the larger ions. The varying times of flight are converted into the different masses of the ions.
An alternative method for ionizing an analyte is electrospray (or ES). Like MALDI, electrospray allows for the ionization/vaporization of polar molecules. Initially the sample of interest is dissolved in a solvent where, to a certain extent, it will exist in an ionized form. In conventional ES, the solution is then pumped through a thin capillary which is raised to a high potential. Small charged droplets are sprayed from the ES capillary into a bath gas at atmospheric pressure and travel down a pressure and potential gradient towards an orifice in the mass-spectrometer high-vacuum system. As the droplets traverse this path, they become desolvated and reduced in size such that surface-Coulombic forces overcome surface-tension forces. As a result, the droplets break up into smaller droplets until either an ion desorbs from the droplet or the solvent is completely removed. The exact mechanism of ion formation is not entirely clear, but the result is a beam of ions, which are sampled by the mass spectrometer. A more detailed description of the ES process is provided in Electrospray Ionization Mass Spectrometry: Fundamentals, Instrumentation and Applications edited by Cole (John Wiley and Sons, New York).
Whichever ionization method used, the formation of unwanted adducts during ionization can compromise the quality and resolution of spectra generated by mass spectrometry. More specifically, the presence of unwanted adducts can make it difficult to detect and analyze an analyte, especially low abundance or low mass analytes.

This patent is subject to a terminal disclaimer.

Compositions and processes for improved mass spectrometry analysis


A recipient communications device associated with a vehicle computing system (VCS) may be configured to receive, over a communications network, an incoming communication from a sender communications device, identify a notification type to provide based on a message directive provided by the sender device, retrieve notification settings associated with the notification type, and perform a notification of receipt of the incoming communication using a VCS user interface according to the notification settings.

Mobile phones may allow users to associate different ring tones with different contacts or groups of contacts. Mobile phones may also allow users to automatically block or ignore contacts or groups of contacts. In some cases, ignoring contacts may be scheduled as being enabled or disabled according to time, user input or device location. However, configuring these contact or group-specific settings may be tedious and likely to become out-of-date, and the block or ignore settings may relate only to contacts stored on and known to the mobile phone. Moreover, blocked contacts may attempt to overcome the block or ignore settings by performing actions such as performing multiple calls in a row.

Categorized handling of electronic communications


A camera mount, comprising a camera mounting portion, wherein a camera can be removably coupled to the camera mounting portion, such that a photographic plane of the camera is parallel to a photographic plane of the camera mounting portion; a rail portion, wherein the rail portion extends from the camera mounting portion substantially perpendicular to the photographic plane of the camera mounting portion; and a frame, wherein the frame is adapted to receive one or more reference scales such that a photographic plane of the one or more reference scales is parallel to a photographic plane of the camera mounting portion, and wherein the frame is coupled to the rail portion such that a photographic plane of the frame is parallel to a photographic plane of the camera mounting portion elements.

1. Field of the Invention
The present invention relates to a device to reduce distortion in photogrammetry. More specifically, the present invention is drawn to a device that reduces or eliminates distortion in forensic photography.
2. Description of Related Art
Photogrammetry is the art or science of obtaining reliable measurements by means of photography. Some categories of photography may use a reference or object within the photographed field to give context to the object or location photographed. For example, in forensic photography of evidence, a physical reference scale aids in showing the size, dimension, or orientation of the item photographed. This is sometimes referred to as a category of forensic, close in photogrammetry.
Forensic photography is used in both civil and criminal proceedings, where the accuracy of recording relevant information is important. The U.S. Federal Bureau of Investigation (FBI) specifies use of an L-shaped reference scale that has a 30 cm long first arm and a 15 cm long second arm, each having a 15 cm straight scale. The scales are graduated and alternate in black and white for visibility. This "Bureau" reference set is sometimes referred to as the photomacrographic scale set.
Crimes that involve bitemarks show dramatically the difficulty of photographing evidence consistently and accurately, in that a bitemark is a difficult subject to photograph. A bitemark is commonly defined as a physical change in an object caused by its contact with the biter's teeth. In other words, a bitemark is the representative pattern left in a bitten object or tissue, which is caused by the impression of the dental structure of the biting animal or person. A typical human bitemark is an oval patterned injury having two opposing, U-shaped arches, separated at their bases where the upper and lower jaws come together. On the edges of the arches may be additional abrasions, contusions, or lacerations caused by the teeth.
Bitemark characteristics can be used to identify the biter. The characteristics of bitemarks fall into "class" and "individual" characteristics. Class characteristics are common to a group, and can be used to distinguish groups, such as a bitemark of a child from a bitemark of an adult. Individual characteristics differentiate between individuals and may lead to the identity of the specific biter or perpetrator. The number, specificity, and accuracy of reproduction of individual characteristics within a bitemark improve the confidence of bitemark identification.
Odontology is the study of the structure, development, and abnormalities of teeth. When applied to forensics, odontology (or forensic dentistry) includes the legal, evidentiary aspects of investigative dentistry, such as the study of bitemark characteristics with the object of ascertaining the facts surrounding a biting. Thus, odontology is a specialized role in effective crime scene investigation.
An early step in processing the evidence of any crime scene is to photograph the scene using still photography and other visual media. The standards for photographic documentation of a bitemark are provided within the American Board of Forensic Odontology (ABFO) Bitemark Analysis Guidelines. According to the guidelines, photography is preferably performed under an odontologist's direction to ensure accurate and complete documentation of the bite site.
Bitemark analysis guidelines state that an ABFO No. 2 metric scale should be used in order to demonstrate, within the photographs, the size and spatial relationship of bitemark characteristics. The ABFO No. 2 metric scale features both linear and circular graduations in the horizontal and vertical directions. Three crosshair circles aid in compensating for distortion from oblique camera angles. Contrasting measuring bars, 18% gray scale, and the L-shape further enable odontologists to analyze the relative location, size, and orientation of the characteristics of a bitemark from a photograph.
Correct placement of the ABFO No. 2 scale is critical to accurate photographic recordation of bitemark characteristics. The L-shaped scale should be situated on the same plane and adjacent to the bitemark. The critical close-up photographs should be taken in a manner that eliminates distortion that could interfere with a determination of the characteristics of the bitemark.
For example, when the ABFO No. 2 scale and the injury are on the same plane, but the camera angle is not perpendicular to that plane, then the resulting photograph will be subject to angular distortion. Inaccurate positioning of the bite site, the camera, or the ABFO No. 2 scale can create perspective and parallax distortion of the captured image. With such distortion, otherwise similar photographs may show different photogrammetric characteristics.
There are four general types of photographic distortion associated with L-shaped forensic scales. If any photographic distortion exists, it must be corrected before a meaningful comparison analysis can be accomplished. If the image is severely distorted, the distortion may not be correctable and the photograph(s) may not be useable and the subject matter must be re-photographed. Unfortunately, physical evidence is often short-lived, fragile, or transitory in nature and a second photographic opportunity will not be available.
The first type of photographic distortion, Type I angular distortion, occurs when a scale is positioned parallel to the plane of the photographic subject, but the camera is not perpendicular to the plane of the scale and the photographic subject. For example, the scale and bite mark are co-planar, but the plane of the camera back is not parallel to the plane of the scale and bite mark.
The second type of photographic distortion, Type II distortion, occurs when the scale is not in the same plane as the photographic subject (i.e., the bite mark). Thus, the proportions of the photographic subject (i.e., the injury pattern) are not accurately ascertainable.
The third type of photographic distortion, Type III distortion, occurs when one leg of a two-dimensional scale has perspective distortion but the other leg does not. Again, the proportions of the photographic subject (i.e., the injury pattern) are not accurately ascertainable.
The fourth type of photographic distortion, Type IV distortion, occurs when the scale itself is skewed. For example, a portion of the scale is bent, twisted, or curled.
While these are not the only types of potential photographic distortion, these encompass most of the physical distortion seen in evidentiary photographs, such as, for example, bite mark photographs.
The bitemark photographs are recorded within the crime scene photographic log, and become part of the descriptive evidence of the crime scene. The close-up bitemark photographs are important to enable subsequent analysis of the bitemark characteristics by an odontologist.
During analysis of the bitemark photographs, the odontologist will determine a number of facts regarding the bitemark, such as anatomical location, surface and skin characteristics, underlying structure, the shape of the bitemark, (e.g. essentially round, ovoid, crescent, etc.), color, size (i.e., vertical and horizontal dimensions of the bitemark), types of injuries (e.g., petechial hemorrhage, contusions, incisions, etc.), position of maxillary and mandibular arches, location and position of individual teeth, intradental characteristics, etc. The forensic odontologist will then compare the bitemark characteristics from the crime scene with photographs, plaster casts, and/or other evidence from examination of a suspect, which typically includes the results of an intra-oral examination.
Frequently, however, an odontologist is not among the first responders to perform the photographic recordation of a crime scene. Access to the victim after the crime may also be limited for a variety of reasons. Thus, a first responder, who may have minimum photographic training and possibly none in bitemark photography, may be required to photograph the bitemark. Depending on the nature of the incident and sensitivity of the occurrence, the first responder may have limited time to record the bitemark characteristics correctly.
The wide angle orientation photograph may well be within the capability of a first responder trained in general photography. However, the first responder may be unfamiliar with the peculiar requirements for close-up photography of a bitemark. In particular, a first responder is unlikely to have sufficient training in the proper use of the ABFO #2 scale to accurately record the bitemark characteristics.
Unfortunately, this can lead to distortion, unreliable photographs, and nonstandard characterization of the bitemark.

Device for reduction of angular distortion in photograpy


A method and apparatus for mixing and dispensing two fluids from a nozzle comprises a mixing chamber for the two fluids defined by the nozzle. A first fluid of the two fluids is sprayed into the mixing chamber from a first aperture within the nozzle and a second fluid from a second aperture within the nozzle is sprayed into the mixing chamber. The second aperture is oriented in a direction within the nozzle such that the fluid dispensed therefrom is incident upon the first aperture for cleaning the first aperture.

As is well known, a variety of beverages are marketed to retail consumers by dispensing systems which simultaneously deliver a metered quantity of flavored syrup with a proportional quantity of carbonated water or the like. Due to sanitation and economic concerns, the beverage industry typically supplies these flavored syrups in collapsible bag-in-box containers which are adapted to be connected to suitable prior art dispensing systems.
The majority of the prior art dispensing systems utilize low flow rate pumps for drawing the syrup from the bag container to supply a metered quantity of the syrup to a mixing nozzle. The use of such low flow rate pumps has improved system reliability.
Syrups are normally concentrated and mixed with relatively large volumes of carbonated water. Therefore, undesired small variations in the relative quantity of carbonated water or syrups supplied will produce wide variations in the taste and quality of the final mixed product.
Although prior art dispensing systems have generally proven suitable for their intended purposes, they possess inherent deficiencies which have detracted from their overall effectiveness and use in the trade. Foremost among these deficiencies is the inability of prior art dispensing systems to precisely regulate the volume of the two fluids being dispensed. Prior art dispensing systems generally meter the two fluids by attempting to regulate their respective flow rates. The regulation of fluid flow rate has the inherent deficiency that the volume of fluids thus dispensed is dependent upon their respective pressures, viscosities, and temperatures. Therefore, attempts to control the flow of fluids thus dispensed is not sufficient to insure the quality of the beverages thus produced.
Since the quality of the beverage is dependent primarily upon the ratio of the flavored syrup to the carbonated water used to produce the beverage and since small variations in this ratio can produce wide variations in the taste of the beverage, it is therefore desirable to regulate this ratio as precisely as possible. Thus, there exists a substantial need in the art for a reliable, relatively inexpensive apparatus and method for dispensing flavored syrup and carbonated water or the like in fixed proportions to insure the quality of the beverage thus produced.

Method and apparatus for facilitating the cleaning of a spray aperture in a mixing chamber of a nozzle


A power semiconductor drive circuit includes a parallel circuit connected to a gate of a power semiconductor element and constituted by two transistors for setting gate resistance of the power semiconductor element; a gate voltage monitoring circuit connected to the gate of the power semiconductor element and the parallel circuit, wherein a monitoring voltage is set in the gate voltage monitoring circuit to monitor a gate voltage of the power semiconductor element; a signal delay circuit to delay an output signal of the gate voltage monitoring circuit; and a gate control circuit to change the magnitude of combined resistance of the parallel circuit based on an output signal output from the signal delay circuit.

Power semiconductor elements may include, for example, IGBT (Insulated Gate Bipolar Transistor), power MOSTFET (Metal Oxide Semiconductor Field Effect Transistor), MOSGTO (MOS Gate Turn-off Thyristor) and the like. Further, an Intelligent Power Module (hereinafter referred to as an IPM) may include a power semiconductor circuit integrating these power semiconductor elements and a power semiconductor drive circuit for controlling gates of the power semiconductor elements, and circuit devices other than the power semiconductor circuit, which are packaged in a single package.
FIG. 11 schematically shows a power semiconductor drive circuit, a power semiconductor circuit and a power module circuit device. As shown in FIG. 11, drains D of transistors M2 and M3 are connected in common and this common connection point is connected to a node HO and a gate G of a transistor PT1. Gates G of transistors M2 and M3 are connected in common and an upper input signal HIN is applied to these common gates G via an upper driver UD. A power supply voltage VBB is applied to a source S of the transistor M2 via an external terminal VB. The power supply voltage VBB is a power supply voltage VCC supplied to an external terminal VC and a boost voltage generated in a bootstrap circuit BS. A source of the transistor M3 is connected to a node VS.
The transistor PT1 is referred to as an upper power transistor and a power supply voltage VPP is applied to a drain D of the transistor PT1 via an external terminal P. The gate G of the transistor PT1 is connected to the node HO. A source S of the transistor PT1 is connected to the node VS. A diode for free-wheeling (shown without a reference sign) is connected between the drain D and the source S of the transistor PT1.
A transistor PT2 is generally referred to as a lower power transistor and is fabricated on a separate semiconductor substrate from the transistor PT1 referred to as the upper power transistor. A wire LW made of material such as aluminum or copper is used as a connector for connecting the transistor PT1 and the transistor PT2. The wire LW has a first end connected to the node VS and a second end connected to an output terminal OUT and a drain D of the transistor PT2. The wire LW has an inductance component lw.
The drain D of the transistor PT2 is connected to the output terminal OUT, a source S of the transistor PT2 is connected to a ground electric potential GND via an external terminal N, and a lower input signal LIN is applied to a gate G of the transistor PT2. A diode for free-wheeling (shown without a reference sign) is connected between the drain D and the source S of the transistor PT2, like the transistor PT1. The transistor PT2 is turned on/off complementarily with the transistor PT1. That is, the transistor PT1 is OFF when the transistor PT2 is ON, and the transistor PT1 is ON when the transistor PT2 is OFF.
A capacitor CB for bootstrap is connected between the external terminal VC and the external terminal OUT. The external terminal OUT is connected to an external load. As the external load, an inductor L1 is shown. The inductor L1 directly indicates an inductor, for example, employed for a switching regulator, a motor winding, and a three-phase winding used for an inverter.
In the power semiconductor drive circuit and the like shown in FIG. 11, if a switching speed of the transistor PT1 is high, problems may occur where a transient voltage ΔV is generated by the inductance component lw of the wire LW and the transistors M2 and M3 deteriorate or are destroyed. In addition, if a switching speed of the transistor PT2 is high, gate capacitances Crss and Ciss of the transistor PT1 are charged and a gate voltage of the transistor PT1 exceeds a threshold voltage Vth of the transistor PT1. Accordingly, the transistor PT1 which should be originally placed in an OFF state is self-turned on and a through-current flows between the transistor PT1 and the transistor PT2, which may result in a problem of deterioration of the transistors PT1 and PT2. In addition, without leading to the deterioration, power may be wastefully consumed, which may result in difficulty in achieving power saving.
As a first solution to solve the above problems, the driving ability of a voltage-driven element may be lowered by changing a switching element of a parallel circuit when a gate voltage at the time of turning-on reaches a mirror voltage.
A second solution may include detecting a change in gate voltage by a comparing circuit and changing gate resistance based on the detection.
As a third solution to realize the compatibility of EMI noise suppression and switching loss suppression at low costs, a power device control circuit may employ a time constant circuit composed of a resistive element and a capacitor, as a timer circuit so as to equalize periods taken for a gate voltage to reach a mirror voltage.
However, the first solution still has a risk of a breakdown of a gate driver due to a surge or a transient voltage generated according to an operation of switching from an ON state to an OFF state.
The second solution requires a relatively complicated timer circuit for detecting a timing at which an element at a high electric potential side is switched from OFF to ON or from ON to OFF, and setting a predetermined voltage based on this detection.
Although the third solution suppresses the EMI noise, it cannot expect to suppress breakdown of a power semiconductor drive circuit and switching loss of a power semiconductor.

Power semiconductor drive circuit, power semiconductor circuit, and power module circuit device


A multiple docking system allows multiple dock units to be connected to the bus of a primary unit notebook computer. This is accomplished using multiple bridges between the primary bus of the primary unit and secondary buses in each of the dock units. Importantly, the system allows for hot docking or docking of the multiple dock units to the primary unit while the primary unit is operational. It accomplishes this, however, without the latency impact associated with buffers on the primary bus. Instead, a docking signal is generated to a bridge in first dock unit as the second dock unit is docked. This causes the bridge to complete bus transactions between the primary bus and the first dock unit's secondary bus. The bridge also generates a float request signal to the primary unit and then floats the secondary bus only after receiving a float grant signal back.

Computers have been designed with accessible bus connectors that provide external electrical connections to their buses. This configuration is most common in portable and specifically notebook-size computers and is used in two scenarios. The bus connector may be used to connect the portable computer to a non-portable docking station that many times allows connection to a larger display and a full size keyboard. In other implementations, the bus connector is adapted to be connected to somewhat portable dock units that can contain hard drives, CD ROMS, and power supplies. Compatible dock units are available that have larger battery power supplies, CD ROMS, and other capabilities for multimedia functions, for example.
One issue that arises when providing this docking capability is how to handle the physical electrical mating between the computer, or primary unit, and the dock unit. Glitches or anomalous voltages will arise on the primary bus when the primary bus makes electrical contact with the corresponding connector on the dock unit's bus extension. Such glitches can cause the primary unit to hang or become inoperable, requiring rebooting.
One solution to handling the docking and the resulting glitches on the bus is to render docking illegal when the primary unit is operational. This solution solves the problem of compensating for the glitches, but is somewhat unacceptable to most users. Another solution is to provide buffers between the primary bus and the primary unit's bus extension. During operation, these buffers act as relay agents that simply pass-on valid bus activity between the primary bus and extension in the dock unit. During docking, however, they prevent the glitches from appearing on the primary unit's bus and, thus, insulate the primary unit. The problem with the buffer solution is two-fold. The buffers: 1) add expense to the primary unit since they represent an additional hardware system; and 2) slow transactions between the primary bus and the dock unit's bus extension.
Another approach is to generate a dock request signal just prior to the physical connection between the primary unit's bus conductors and those of the dock unit; the primary unit electrically floats the primary bus in response to receiving this request signal. The solution, while allowing hot docking or docking while the primary unit is operational, avoids the delay and costs associated with the hardware buffers. The problem, however, is that established protocols do not allow the docking of a second dock unit to dock/primary unit pairs.


Method for correcting the length of marks and lands representing information taken from an optical disk is disclosed. The method includes digitizing amplified analog data having marks and lands played back from an optical disk and providing a data synchronization clock by using a phase lock loop (PLL). The method further includes providing an adjustment to a threshold signal level based upon the difference in timing position in mark and land edge marks with reference to the data synchronization clock and changing the data mark and land lengths with reference to the adjusted threshold signal.

There is a need in reading information from an optical disk which is to provide correction of distorted mark and land lengths. A systematic error is that which affects all consecutive mark edge positions in a predictable way over some period of time, generally greater than two bytes. In an optical recording system, systematic error is caused by the following: focus and tracking errors, write power error, media sensitivity variation, optical aberrations, and stamper imperfections in the case of etched or molded media. Systematic mark length error is a problem because it limits the data capacity and reliability that can be achieved for a given system.
The current state of the art uses multiple phase locked loops (PLLs) or a single phase locked loop as a data edge position reference for detecting length errors. Reference is made to assigned U.S. Pat. No. 4,734,900 granted Mar. 29, 1988 to IBM entitled "Restoring And Clocking Pulse Width Modulated Data."
The basis of a PLL data correction circuit is to monitor the timing difference between the played back data edges, and the previously synchronized data clock generated by the PLL. The detected timing difference or "error" is then fed back into the circuit to provide a way for changing the data edge positions. Conventionally, the PLL positions the clock edges to equalize the timing difference between the leading data edge and clock edge and the trailing data edge and clock edge. This relationship can be used to measure systematic error in the length of the data. When there is a length error, the leading and trailing data edges are offset in equal and opposite directions relative to the clock edges. The direction and length of the error can be determined by the relative position of the data edges (leading or trailing) to the clock edges. A duty cycle correction circuit measures these data and clock edge position differences and feeds the correction back into the data channel in either open or closed loop configurations. The maintenance of ideal edge positions i.e. when clock and data edges are superimposed, provide maximum margin for any single edge to leave the detection window causing a bit error. As a result, the number of bit errors produced by the system is minimized.
There are three fundamental correction techniques outlined in the IBM patent. In this patent, the first is a dual phase locked loop approach wherein a first phase lock loop PLL A is locked to the leading edges of the pulse length modulated data, and a second phase lock loop PLL B is locked to the trailing edges of the data. An error signal is then generated by monitoring the phase difference between the two clock signals generated by the PLL's A and B. The problems with a multiple phase lock loop (PLL) approach are complexity, and opportunity for interactions between the loops causing oscillations. A second technique described employs a single PLL, however, it utilizes two one shot multivibrators to provide the corrected data signal, one fixed and one variable. The problem with this solution is that "one shots" are very unstable devices where response varies greatly with temperature and component variations making the solution unstable and inconsistent. A second problem with this approach is that only one edge is being shifted relative to the clock forcing the PLL to adjust as the data lengths are being corrected. If two `one shots` were used, one per edge, the variation in response of each `one shot` with respect to the other could result in very different leading and trailing edge position responses to timing errors. This solution can lead to residual length errors, instability and interaction when submitted to certain disturbances. Correction bandwidth will be limited to PLL response. A third technique described uses a very high speed clock and counter to monitor the data edge position relative to the system clock edge to generate an error signal. This system has the problem of requiring a very high frequency clock, on the order of fifty times the data rate. Clock frequencies of this order will cause electromagnetic interference (EMI) and other problems that would be extremely difficult and costly to contain in a computer peripheral environment.

Correcting recorded marks and land lengths taken from an optical disk