A bipolar transistor (10) is formed by using low temperature epitaxial deposition in order to form a base layer (14) of the transistor (10). A dielectric (16, 17, 18) is applied to the base layer (14) and an emitter opening (21) having sloping sidewalls is formed in the dielectric (16, 17, 18). Low temperature epitaxial deposition is also used for forming an emitter (24) within the emitter opening (21). The emitter opening (21) forms sloping sidewalls on the emitter (24) thereby forming an emitter overhang that overlies the base layer (14). The width (26) of the emitter overhang determines an extrinsic base width of the transistor (10).

The present invention relates, in general, to semiconductor devices, and more particularly, to bipolar transistors.
In the past, the semiconductor industry has utilized a variety of methods to form bipolar transistors. One problem associated with the prior methods is controlling dopant distributions within the transistor's base. Prior transistor formation methods require either emitter implant annealing, oxide sidewall formation, or other high temperature (above 900.degree. C. Celsius) operations that disturb dopant distributions within the transistor's base layer. Such methods often result in a transistor having high base leakage current that degrades the transistor's efficiency. Additionally, disturbing the dopants modifies the transistor's current gain.
In addition, the bipolar transistors formed by the prior implementation methods generally have non self-aligned emitter-base contacts. Consequently, extra space must be provided between the emitter and base contacts in order to ensure that the contacts do not overlap. The extra space increases the transistor's cost, and increases base resistance thereby degrading the transistor's performance.
Accordingly, it is desirable to have a method of forming a bipolar transistor that does not disturb base dopant profiles, that results in a transistor having low base leakage current, that provides accurate control of the transistor's current gain, and that has self-aligned emitter-base contacts.

Method of forming a bipolar transistor having an emitter overhang


A traffic scheduling system and method for packet-switched communications networks where multiple sessions share an outgoing communications link. Prior to transmission on the outgoing link, packets are assigned a time-stamp and placed into a priority queue in order of ascending time-stamps so that the packet with the smallest time-stamp is placed at the head of the queue. The time-stamp assigned to a particular packet is calculated as the estimated time at which the last bit of the packet is transmitted in an ideal system, using a global variable called the system potential which tracks the progress of work in the scheduling system. The system potential is recalibrated periodically to avoid any long-term unfairness in service offered to the sessions sharing the outgoing link.

1. Field of the Invention
This invention pertains generally to traffic scheduling systems for packet-switched communications networks and, more particularly, to a system and method for carrying out such traffic scheduling providing low end-to-end delay bounds, low buffer requirements, and fairness.
2. Description of the Background Art
As computer networks become more and more widespread, methods for controlling traffic efficiently in these networks are becoming more important. Early data networks were based on circuit switching where the peak bandwidth demand of a communication session was allocated to it for the entire duration of the session. When the session traffic was bursty, that is when the peak rate of the session exceeded its average rate, circuit switching resulted in under-utilization of the network resources. Packet switching was developed to overcome this disadvantage, thus improving the network utilization for bursty traffic.
Packet switched networks dynamically allocate bandwidth according to demand. By segmenting the input flow of information into units called "packets," and processing each packet as a self-contained unit, packet switched networks allow scheduling of network resources on a per-packet basis. This enables multiple sessions to share the network resources dynamically by allowing their packets to be interleaved across the communication network.
Along with the introduction of packet switched networks came a desire for Quality of Service (QoS) guarantees. Many future applications of computer networks such as distance education, remote collaboration, and teleconferencing will rely on the ability of the network to provide QoS guarantees. These guarantees are usually in the form of bounds on end-to-end delay of the session, bandwidth, delay jitter (variation in delay), packet loss rate, or a combination of these parameters. Broadband packet networks based on ATM (Asynchronous Transfer Mode) are currently enabling the integration of traffic with a wide range of QoS requirements within a single communication network. QoS guarantees can also be provided in conventional packet networks by the use of proper methods in the packet switches (or routers).
Providing QoS guarantees in a packet network requires the use of traffic scheduling methods in the switches (or routers). The function of a scheduling method is to select, for each outgoing link of the switch, the packet to be transmitted in the next cycle from the available packets belonging to the communication sessions sharing the output link. This selection must be performed such that the QoS guarantees for the individual traffic sessions, such as upper bounds on maximum delay, are satisfied. Implementation of the method may be in hardware or software. Because of the small size of ATM cells, the scheduling method must usually be implemented in hardware in an ATM switch. In a packet network with larger packet-sizes, such as the current Internet, the method can be implemented in software.
Several methods have been proposed for traffic scheduling in packet switches. In general, schedulers can be classified as work-conserving or non-work-conserving. A scheduler is work-conserving if the server is never idle when a packet is buffered in the system. A non-work-conserving server may remain idle even if there are available packets to transmit. A server may, for example, postpone the transmission of a packet when it expects a higher-priority packet to arrive soon, even though it is currently idle. When the transmission time of a packet is short, as is typically the case in an ATM network, however, such a policy is seldom justified. Non-work-conserving methods are also used to control delay jitter (variation in delay) by delaying packets that arrive early. Work-conserving servers always have lower average delays than non-work-conserving servers and are therefore preferred for most applications.
Examples of work-conserving schedulers include Generalized Processor Sharing (GPS), Weighted Fair Queueing, VirtualClock, Delay-Earliest-Due-Date (Delay-EDD), Weighted Round Robin, Deficit Round Robin, and Hierarchical-Round-Robin. Examples of non-work-conserving schedulers include Stop-and-Go queueing, and Jitter-Earliest-Due-Date.
Another classification of traffic schedulers is based on their internal architecture: This classification gives rise to two types of schedulers--sorted-priority and frame-based. Sorted-priority schedulers compute a time-stamp, associated with each packet in the system. Packets are sorted based on their time-stamps, and are transmitted in that order. VirtualClock, Weighted Fair Queueing, and Delay-EDD follow this architecture. To aid in the computation of time-stamps, sorted-priority schedulers usually maintain a global function that keeps track of the progress of work in the system. This global function is often referred to as "virtual time." Two factors determine the implementation complexity of all sorted-priority methods. The first is the complexity of updating the priority list and selecting the packet with the highest priority is at least O(log V) where V is the number of connections sharing the outgoing link. The second is the complexity of calculating the time-stamp associated with each packet; this factor depends heavily on the method. For example, maintaining the virtual time in Weighted Fair Queueing requires the processing of a maximum of V events during the transmission of a single packet, whereas time-stamps in VirtualClock can be calculated in constant time, that is O (1).
In a frame-based scheduler, a virtual time is not calculated. Frame-based schedulers split time into frames of fixed or variable length. Reservations of sessions are made in terms of the maximum amount of traffic the session is allowed to transmit during a frame period. Hierarchical Round Robin and Stop-and-Go Queueing are frame-based schedulers that use a constant frame size. As a result, the server may remain idle if sessions transmit less traffic than their reservations over the duration of a frame, making them non-work-conserving. In contrast, Weighted Round Robin and Deficit Round Robin schedulers allow the frame size to vary within a maximum. Thus, if the traffic from a session is less than its reservation, a new frame can be started early. Therefore, both Weighted Round Robin and Deficit Round Robin are work-conserving schedulers.
Many different scheduling methods have been proposed to approximate the theoretical scheduling discipline known as Generalized Processor Sharing (GPS). The GPS discipline is defined with respect to a "fluid model," where data transmitted by each session is considered to be infinitely divisible and multiple sources may transmit their data simultaneously through a single physical communication link. This allows tight control of the bandwidth allocated to each session on a link. Unfortunately, GPS is only a hypothetical scheduling discipline. In practice, the packets transmitted by each session cannot be divided further, and data from multiple sessions can be interleaved only at packet boundaries. Thus the GPS discipline cannot be implemented in practice in a packet-switched network. However, the GPS discipline provides a sound theoretical basis for the design of practical scheduling methods. A number of such practical methods have been designed based on GPS. These methods vary in their end-to-end delay bounds (that is, the maximum delays seen by packets from a particular session in the network between its end nodes), the level of fairness achieved in allocating bandwidth to different sessions sharing the same communication link, and the complexity of implementing them in a switch or router. An outline of the GPS scheduling discipline is given below, before describing previous methods based on GPS.
Assume that the GPS discipline is used to schedule traffic on an outgoing link of a switch. The share of bandwidth reserved by session i on the outgoing link is represented by a real number .phi..sub.i. Let B(.tau.,t) denote the set of sessions that have at least one packet in the switch at all times during the interval (.tau., t). If r is the bandwidth capacity of the outgoing link, the service offered to a connection i denoted by W.sub.i (.tau.,t) is proportional to .phi..sub.i. That is: ##EQU1## The minimum service that a session can receive in any interval of time is: ##EQU2## where V is the maximum number of sessions that can be backlogged in the server at the same time. Thus, GPS serves each backlogged session with a minimum rate equal to its reserved rate at each instant; in addition, the excess bandwidth available from sessions not using their reservations is distributed among all the backlogged sessions at each instant in proportion to their individual reservations. This results in perfect isolation, ideal fairness, and low end-to-end session delays. Recall that the end-to-end session delay is the delay experienced by a packet between the time it leaves a source and the time it is received at its destination.
Unfortunately, as indicated above, GPS is only a theoretical system and not directly implementable in practice. Therefore, systems have been designed to approximate the GPS system as closely as possible. An example is a packet-by-packet version of the GPS method, known as PGPS or Weighted Fair Queueing as defined in A. Demers, S. Keshav, and S. Shenker, "Analysis and Simulation of a Fair Queueing Method," Internetworking: Research and Experience, Vol. 1, No. 1, pp. 3-26, 1990. Unfortunately, there is a serious shortcoming with the Weighted Fair Queueing method which will be apparent after the following brief discussion of the Weighted Fair Queueing method.
In the Weighted Fair Queueing method, we assume that each traffic session i sharing the output link controlled by the scheduling method is assigned a value .phi..sub.i corresponding to the reserved bandwidth of the session. The values .phi..sub.i are computed such that the reserved bandwidth of session i on the link is given by ##EQU3## where the denominator computes the sum of the .phi..sub.i values for all the sessions sharing the link.
In the Weighted Fair Queueing method, a GPS fluid-model system is simulated in parallel with the actual packet-by-packet system, in order to identify the set of connections that are backlogged in the GPS system and their service rates. Based on this information, a time-stamp is calculated for each arriving packet, and the packets are inserted into a priority queue based on their time-stamp values. To accomplish the time-stamp calculation, a virtual time v(t) is maintained by the scheduler. This virtual time v(t) is a piece-wise linear function of the real time t, and its slope changes depending on the number of busy sessions and their service rates. More precisely, if B(.tau.,t) represents the set of backlogged connections (by "backlogged" we mean that the session has one or more packets buffered in the switch throughout the time interval under consideration) in the scheduler during the interval (.tau., t), the slope of the virtual clock function during the interval (.tau.,t) is given by: ##EQU4##
On the arrival of a new packet, the virtual time v(t) must first be calculated. Then, the time-stamp TS.sub.i.sup.k associated with the k-th packet of session i is calculated as: ##EQU5## where TS.sub.i.sup.k-1 is the time-stamp of the previous packet of session i, L is the size of the k-th packet, and .phi..sub.i is the share of the bandwidth allocated to session i.
A serious limitation of the Weighted Fair Queueing method is its computational complexity arising from the parallel simulation of the fluid-model GPS scheduler that is required for computation of virtual time v(t). If there is a total of V sessions sharing the outgoing link, a maximum of V events may be triggered in the simulation during the transmission time of a single packet. Thus, the time for completing a scheduling decision is O(V). When the number of sessions sharing the outgoing link is large, this computation time can be prohibitive. In particular, the method is difficult to apply in an ATM switch where the transmission time of a cell is small (approximately 2.7 microseconds with 155.5 Mbits/second link speed).
A method to reduce the complexity of Weighted Fair Queueing, using an approximate implementation of GPS multiplexing, was proposed in J. Davin and A. Heybey, "A Simulation Study of Fair Queueing and Policy Enforcement," Computer Communications Review, Vol. 20, pp. 23-29, Oct. 1990, and was later analyzed in S. Golestani, Proceedings of INFOCOM '94, pp. 636-646, IEEE, April 1994 under the name "Self-Clocked Fair Queueing" (SCFQ). In this implementation, the virtual time function v(t) is approximated using the time-stamp of the packet currently in service. Let TS.sub.current denote the time-stamp of the packet currently in service when a new packet arrives, and let the new packet be the k-th packet of session i. Then, the time-stamp of the new packet is calculated as: ##EQU6## where TS.sub.i.sup.k-1 is the time-stamp of the previous packet of session i, L is the size of the k-th packet, and .phi..sub.i is the share of the bandwidth reserved by session i. This approach reduces the complexity of the method greatly. However, the price paid is the reduced level of isolation among the sessions, causing the end-to-end delay bounds to grow linearly with the number of sessions that share the outgoing link. This can be a very problematic limitation of this method because the worst-case delay of a session can no longer be controlled just by controlling its reservation, as is possible in Weighted Fair Queueing. The higher end-to-end delay also affects the burstiness of sessions within the network, increasing the buffer requirements. Here, burstiness refers to the behavior of session traffic where its actual rate of arrival during a specified interval of time is larger than its average rate. Thus, a high burstiness generally implies a large number of packets arriving close together in time, with long idle intervals in between.
Another well-known scheduling method is VirtualClock, described in L. Zhang, "VirtualClock: a new traffic control algorithm for Packet switching networks," ACM Transactions on Computer Systems, vol. 9, pp. 101-124, May 1991. This method provides the same end-to-end delay and burstiness bounds as those of Weighted Fair Queueing with a simple time-stamp computation method, but the price paid is in terms of fairness. A backlogged session in the VirtualClock server can be starved for an arbitrary period of time as a result of excess bandwidth it received from the server when other sessions were idle.
What is needed is a method and apparatus that calculates and maintains a global parameter for keeping track of the progress of the system in a distinct and more accurate manner than the virtual time based methods described above. This global parameter should provide implementation complexity similar to that of Self-Clocked Fair Queueing, but still maintain the delay bounds of Weighted Fair Queueing. What is further needed is a method and apparatus that provides for maximum fairness among all incoming connections to the system.

Traffic scheduling system and method for packet-switched networks

The Regents of the University of California


Method and apparatus for installing a support member to support a flexible element, such as a shipping comb used to support a flexible suspension assembly of a head-stack assembly (HSA). A robotic end effector configured to insert the support member to bias the flexible element. Prior to said insertion, an inspection assembly verifies at least one physical parameter of the member while the member is supported by the end effector. One or more computerized video images along at least one axis are preferably obtained by the inspection assembly, and machine readable code on the member is preferably decoded from said image(s). The end effector preferably includes a pair of opposing gripper fingers which engage the support member with variable compressive force during insertion. A cleaning assembly preferably cleans the support member prior to insertion, and a subsequent video image is preferably obtained after insertion to verify installation of the member.

Data storage devices are used to access computerized data in a fast and efficient manner. The data are stored on storage media, such as one or more axially aligned magnetic recording discs accessed by a corresponding array of data transducers.
A moveable actuator, also referred to as a head stack assembly (HSA), can be used to controllably advance the transducer(s) adjacent the media. In a disc drive data storage device, the transducers are often supported by flexible suspension assemblies (flexures) which in turn are mounted to rigid actuator arms. The arms are configured for pivotal movement about a pivot bearing assembly located adjacent an outermost diameter of the media.
The HSA further supports a coil which is immersed in a magnetic circuit of a voice coil motor. The application of controlled voltage across the coil generates a magnetic field that interacts with the magnetic circuit. This induces rotation of the actuator body about the pivot bearing assembly, and radial movement of the transducers across the media surfaces.
It is generally desirable to handle the HSA with extreme care during manufacturing and installation to reduce the potential for damage to the transducers and the flexures. A shipping comb is often installed to provide temporary support of the respective transducers after the HSA has been assembled. The shipping comb is usually designed to remain in place until such time that the HSA is installed onto a data storage device base deck and the transducers are merged with the media.
With continued advancements in the art, there is a continual need for improvements in the manner in which shipping combs can be reliably and efficiently installed onto head stack assemblies, and it is to these and other improvements that preferred embodiments of the present invention are generally directed.

Automated support member installation station


Catalysts useful for producing methylamines and having practical catalyst life and large selectivity for dimethylamine comprise crystalline silicoaluminophosphate molecular sieves which have a molar ratio of silicon atom to aluminum atom in the range of 0.01-0.30.

1. Field of the Invention
The present invention relates to catalysts for producing methylamines and to method for manufacturing the catalysts. Methylamines, particularly, dimethylamine are important as starting materials for solvents represented by dimethylformamide, rubber products, pharmaceuticals and surfactants
2. Description of the Prior Art
Methylamines are produced usually from methanol and ammonia using solid acid catalysts such as silica-alumina, at a temperature around 400xc2x0 C. Another known method comprises subjecting monomethylamine to a disproportionation reaction. The main product in the above methods for the production of methylamines is trimethylamine which has the least demand. However, dimethylamine is the most useful, and, therefore, methods for selectively producing dimethylamine have been demanded.
Methods for producing methylamines using zeolites which are more advantageous than conventional silica-alumina catalysts have also been proposed. For example, these methods use zeolites such as zeolite A (JP 56-69846 A), FU-1 (JP 54-148708 A), ZSM-5 (U.S.P. 4082805), ferrierite and erionite (JP 56-113747 A), ZK-5, Rho, chabazite and erionite (JP 61-254256 A), and mordenite (JP 56-46846 A, JP 58-49340 A, JP 59-210050 A, and JP 59-227841 A). In addition, there is a method for producing methylamines in an amount exceeding the thermodynamic equilibrium proportion, by using silicoaluminophosphates (JP 2-734 A).
The present inventors filed patent applications, on the basis of findings that silica-modified silicoalumino-phosphates have greater activity and selectivity for dimethylamine than known zeolite catalysts and prior art silicoaluminophosphates (JP Application Nos. 9-197232, 9-360124 and 10-025832). However, the silica-modified silicoaluminophosphate catalysts have a problem of decrease in initial activity, so that a further improvement in life is demanded from a practical point of view.
The object of the present invention is to provide catalysts for producing methylamines which have a practical catalyst life and selectivity for dimethylamine and are free from the problem of decrease in activity encountered in the silicoaluminophosphate catalysts, and also methods for manufacturing the catalysts.
The inventors have found that crystalline silicoaluminophosphates having specific properties and compositional ratios which have never been referred to, in particular, those which are replaced with specific elements or those which are coated with the elements or oxides thereof have smaller decrease of initial activity with time and are effectively improved in catalyst life. As a result, a great improvement is obtained in life of silicoaluminophosphates having excellent initial activity and selectivity for dimethylamine as catalysts for producing methylamines.
The present invention relates to crystalline silicoalumonophosphate catalysts having improved life and being useful as catalysts for producing methylamines which are mainly composed of dimethylamine and produced by a reaction of methanol with ammonia, a reaction of methanol with monomethylamine or a disproportionation reaction of methylamines. The present invention relates also to methods for manufacturing the catalysts.
In more detail, the present invention includes the following aspects.
1) The present invention relates to a catalyst for producing methylamines which comprises a crystalline silicoaluminophosphate molecular sieve having a molar ratio of silicon atom to aluminum atom in the range of 0.01-0.30.
2) The present invention further relates to a method for manufacturing a catalyst for producing methylamines. It comprises mixing an aluminum compound, a phosphorus compound, a silicon compound, an amine or ammonium salt and water so that the molar ratio of them satisfies the following formula (1) when the aluminum compound, the phosphorus compound and the silicon compound are expressed by Al2O3, P2O5 and SiO2, respectively, and then subjecting the mixture to a hydrothermal treatment:
Al2O3.(1xc2x10.2)P2O5.(0.5xc2x10.45) SiO2. (1.5xc2x10.45)Am.(75xc2x125)H2Oxe2x80x83xe2x80x83(1)
wherein Am denotes an amine or ammonium salt having 3 to 24 carbon atoms.
3) The present invention further relates to a method for producing methtylamines which comprises allowing methanol to react with ammonia in the presence of the crystalline silicoaluminophosphate molecular sieve mentioned in the above 1).
4) The present invention further relates to a method for producing methtylamines which comprises subjecting monomethylamine to a disproportionation reaction in the presence of the crystalline silicoaluminophosphate molecular sieve mentioned in the above 1).
For selective production of methylamines, especially, dimethylamine, preference for the molecular sieves is to have an effective micropore size ranging from 0.3 to 0.6 nm. According to the IUPAC structural code of zeolites and their analogous compounds, mention may be made of, for example, 8-membered ring-structural ABW, AEI, AFX, APC, ATN, ATT, ATV, AWW, CHA, DDR, EAB, ERI, GIS, JBW, KFI, LEV, LTA, MER, MON, PAU, PHI, RHO, RTE, RTH, and VNI; 9-membered ring-structural CHI, LOV, RSN, and VSV; 10-membered ring-structural DAC, EPI, FER, LAU, MEL, MFI, MFS, MTT, NES, TON, and WEI; and 12-membered ring-structural AFS, AFY, ATO, CAN, GME, MAZ, MEI, MTW, OFF, RON, and VET.
The present invention uses the crystalline silicoaluminophosphate molecular sieves (SAPO) having the above structures. The crystalline silicoaluminophosphate molecular sieves are products wherein a part of P or Al-P bond is replaced with Si by an isomorphic replacement, in a crystalline aluminum phosphate compound (ALPO) having a chemical composition of the following formula (2) which is represented by oxide mole ratios, excluding crystalline water and organic bases of structure directing agents (for example, JP 57-77015 A):
Al2O3.(1.0xc2x10.2)P2O5xe2x80x83xe2x80x83(2).
Examples are SAPO-17, 18, 26, 31, 33, 34, 35, 37, 40, 41, 42, 44, 47 and 56, and especially preferred are SAPO-17, 18, 34, 35, 44, 47 and 56. Herein, the relationship between the SAPO numbers and their structures is mentioned, for example, in Encyclopedia of Inorganic Chemistry, Vol. 8, 4369 (1994). The IUPAC codes corresponding to SAPO-17, 18, 34, 35, 44, 47 and 56 are ERI, AEI, CHA, LEV, CHA, CHA, and AFX, respectively. The most preferred is SAPO-34 of chabazite structure.
These crystalline silicoaluminophosphate molecular sieves can be relatively readily manufactured using an aluminum compound, a phosphorus compound, a silicon compound, an amine or quaternary ammonium salt as a structure directing agent, and water.
As methods for manufacturing the crystalline silicoaluminophosphate molecular sieves, there are known methods as described in, for example, JP 59-35018 A and a method for manufacturing catalysts for producing methylamine as described in JP Application No. 9-197232 in which the sequence of addition of starting materials or the temperature range is specified. Anyone of the two methods can be employed. various products different in properties can be obtained depending on compositions or pHs of the starting mixtures, orders of addition of the starting materials, varieties of the structure directing agents, and/or conditions of hydrothermal synthesis.
However, in order to obtain those which have large activity and selectivity as catalysts for producing methylamine together with satisfactory catalyst life, it is most important that an atomic ratio of silicon to aluminum which constitute the crystalline silicoaluminophosphate molecular sieves falls within the range of 0.01-0.30. Furthermore, it is preferred that an average crystal grain size of the crystalline silicoaluminophosphate molecular sieves measured by a scanning electron microscope (SEM) is 5 xcexcm or less, that the crystal has a cubic, rectangular parallelepipedic, spheroidal, hexagonal or prismatic form, and that both the size and the form of the crystal are uniform and regular. When the size of the crystal is 5 xcexcm or less and the form of the crystal is as mentioned above, catalyst activity and selectivity are further improved and the catalyst life is further-prolonged.
Atomic ratio of silicon to aluminum should be samll. The larger the ratio, the shorter the catalyst life. However, as the ratio is smaller, crystallinity and form are so degraded that uniform crystals can hardly be obtained. Furthermore, size of crystals becomes uneven. Therefore, the ratio (Si/Al) is preferably in the range of 0.01-0.30, especially preferably in the range of 0.05-0.25. In the case of the above composition (Si/Al), atomic ratio of phosphorus to aluminum is preferably in the range of 0.7-0.9.
As the aluminum compounds used as the starting materials, preferred are pseudo-boehmite and aluminum alkoxides having 3 to 24 carbon atoms, such as aluminum isopropoxide. Pseudo-boehmite is especially preferred because use of it results in the longer crystal life though the reasons are not certain.
As the silicon compounds used as the starting materials, especially preferred are silica, silica sol, orthosilicic acid, and the like. The aluminum compounds and the silicon compounds usually contain alkali metals or alkaline earth metals as impurities. Such impurities usually facilitate an improvement in selectivity in reaction or initial activity as far as they are in a small amount. However, if they are contained in an amount exceeding a certain level, they sometimes have adverse influence on the catalyst life. Accordingly, the content of impurities should be 200 ppm or less.
As the phosphorus compounds used as the starting materials, especially preferred is orthophosphoric acid, but they are not limited thereto.
As the structure directing agents, preferred are amine or ammonium salts having 3 to 24 carbon atoms. Examples of them are trimethylamine, triethylamine, triethanolamine., isopropylamine, dibutylamine, dipentylamine, dihexylamine, piperidine, choline, morpholine, cyclohexylamine, 2-methylpyridine, 4-methylpyridine, tripropylamine, quinuclidine, N-methylcyclohexylamine, N,N-dimethylbenzylamine, N,N-dimethylethanolamine, N,N-25 diethylethanolamine, N,N-dimethylpiperazine, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.
Metals and/or metal compounds can be added to the crystalline silicoaluminophosphate molecular sieves in order to improve methylamine catalysts in respect to activity, selectivity and catalyst life. As the metal species to be added, preferred are Li, Na, Be, Mg, Ca, Sr, Y, Ti, Zr, V, Nb, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Zn, B, Ga, In, Ge, and Sn. Ti, Y and Zr are especially preferred. That is, preferred are crystalline silicoaluminophosphate molecular sieves of H-type in which a part of the H-type is replaced with at least one metal selected from the species mentioned above. Alternatively, the same molecular sieves may be used, as long as they contain the metals or oxides of the metals. Especially preferred are the crystalline silicoaluminophosphate molecular sieves of H-type in which a part of the H-type is replaced with at least one metal selected from Ti, Y and Zr, and the same molecular sieves which contain titanium oxide, yttrium oxide or zirconium oxide.
One of manufacturing procedures for the crystalline silicoaluminophosphate molecular sieves containing the metals and/or the metal oxides is as follows. An aluminum compound, a phosphorus compound, a silicon compound, an amine or ammonium salt and water are mixed with at least one metal and/or a compound of the metal selected from Li, Na, Be, Mg, Ca, Sr, Y, Ti, Zr, v, Nb, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Zn, B, Ga, In, Ge and Sn so that the molar ratio satisfies the following formula (1). The aluminum compound, phosphorus compound and silicon compound are expressed by Al2O3, P2O5 and SiO2, respectively. Then, the mixture is subjected to a hydrothermal treatment.
Al2O3.(1xc2x10.2)P2O5.(0.5xc2x10.45) SiO2.(1.5xc2x10.5)Am.(77xc2x125)xe2x80x83xe2x80x83(1)
wherein Am denotes an amine or ammonium salt having 3 to 24 carbon atoms.
The metal compounds to be added in this case are preferably in the form of water-soluble salts thereof such as nitrates, sulfates and hydrochlorides, Alternatively, metal alkoxides may be used. Furthermore, it is preferred that the metals are contained in an amount of 0.05-20% by weight in the silicoaluminophosphate.
The mixtures are subjected the hydrothermal treatment. The hydrothermal treatment of the starting mixture is carried out in the same manner regardless of whether addition of metals and/or metal compounds have been effected. That is, the treatment is effected until crystalline silicoaluminophosphate is obtained, preferably in a pressurized container having Teflon lining at a temperature of 100-250xc2x0 C. under autogeneous pressure usually over a period of 1-200 hours. Then, the product thus obtained is subjected to filtration, decantation or centrifugal separation in order to separate crystals. In this case, it is preferred to effect repeated washing until the washing water is neutral. Thereafter, the product is dried by keeping it usually at 80-150xc2x0 C. Moreover, the product is calcined in an oxidizing atmosphere such as air or in an air stream at a temperature of 350-700xc2x0 C., preferably 500-600xc2x0 C.
Alternatively, the addition of the metals and/or metal compounds to the crystalline silicoaluminophosphate molecular sieves may be carried out in such a manner that hydrogen in the crystalline silicoaluminophosphate molecular sieves of H-type is replaced with the metals of the metal compounds. The other approach is uniformly mixing the metals or metal oxides with the crystalline silicoaluminophosphate molecular sieves before shaping. The procedures for addition of the metals and/or metal oxides to the crystalline silicoaluminophosphate molecular sieves are not critical. No matter how the procedure may be, the product catalysts are in the form where a part of H-type of the catalysts is replaced with metal elements, or contain the metals or metal oxides.
The crystalline silicoaluminophosphate molecular sieves of the present invention can be suitably used, as they are, as catalysts for a reaction of methanol with ammonia, reaction of monomethylamine with methanol, and conversion reaction to dimethylamine according to a disproportionation reaction of monomethylamine or the like. Moreover, the crystalline silicoaluminophosphate molecular sieves of the present invention can be used for the other catalytic reactions. Furthermore, the present catalyst may be used as admixtures with other suitable molecular sieves. Suitable other molecular sieves to be admixed are, for example, aluminosilicates such as chabazite, mordenite, erionite, ferrierite, epistilbite, clinoptilolite, paulingite, phillipsite, levynite, zeolite-A, rho, ZK-5, FU-1, and ZSM-5. Furthermore, clay minerals such as kaolinite, halloysite, nacrite, montmorillonite, and illite may be optionally selected and added to the crystalline silicoaluminophosphate molecular sieves as binders.
When catalysts comprising the crystalline silicoaluminophosphate molecular sieves of the present invention are used for production of methylamines through a reaction of methanol with ammonia, production of methylamines through a reaction of methanol with monomethylamine, or production of methylamines through disproportionation reaction of monomethylamine, the reactions are conducted, preferably, in a flowing system on a gaseous fixed bed or fluidized bed, or in a system of supplying nitrogen or hydrogen during the flowing.
Reaction temperature in the production of methylamines or in the disproportionation reaction of monomethylamine is preferably 200-400xc2x0 C., especially preferably 250-350xc2x0 C. Reaction pressure is not critical. The reaction can be conducted under reduced pressure or under pressure, but preferably is conducted under pressure of 0.1-10 MPa. Naturally, the embodiments of the present invention are not limited to only the above descriptions.

Catalysts for producing methylamines and method for manufacturing the same


A lightweight, adjustable wrench comprising of a moveable jaw with a reach that is shortened or lengthened with a strap or a cable. The loose end of the strap or cable is secured to the wrench's shank by a cam lock, or similar locking device. Since the strap or cable is the means for the wrench's jaws adjustment, a quicker and easier fit to the pipe or object to be gripped can be obtained. The wrench is more convenient to adjust, since the means for adjustment are located near the handle of the wrench as opposed to the shank end of present designs. The strap or cable adjustment also allows the wrench's shank and handle to be designed hollow and a larger diameter to reduce weight. The wrench can be made in any proportion for any sized application.

This invention relates to the field of devices for gripping pipes, nuts, or the like, and more particularly to a wrench using a strap or a cable as the means to adjust the jaws of the wrench as opposed to a conventional barrel adjusting nut. The purpose of the invention is to lighten the weight of the wrench, reducing the amount of unnecessary metal or material needed to create a strong wrench, thusly reducing production and shipping costs of the invented wrench. A lighter wrench will offer the user greater mobility and result in reduced muscle fatigue.


The all-directional fall sensor of the present invention includes a first casing defining a first interior space filled with a liquid and a floater buoyed by the liquid inside the first casing. The floater includes an indicator having indicative materials therein. The indicator includes a body defining a chamber, which is divided into at least a first portion and a second portion with a first sealing member located therebetween. The indicative materials are contained in the second portion of the chamber and are sealed therein with the first sealing member. When the all-directional fall sensor is applied with a force, the first sealing member would be dislocated and thus the indicative materials are dispersed within the chamber.

1. Field of the Invention
The present invention relates to a fall sensor, especially to an all-directional fall sensor capable of detecting whether a product has suffered a fall or an impact
2. Description of the Related Art
Under the market demand for compact multi-functional electronics with cool design, how to prevent damages to the electronic products caused by accidental dropping is an important aspect to the design of the products. Such prevention is one of the value-added design aspects in the mechanical designs of products. Through experiments and simulations, the mechanical design is amended and shock-absorption materials are added to satisfy the specification requirement for preventing damages due to a drop. However, if during transport or within warranty a product is dropped and broken, and there is no damage readily apparent on the appearance, the maker in this case may have to bear the responsibility for fixing the product.
A buyer of a PDA or a cell phone may sometimes find the PDA or cell phone not functioning after coming home and opening the box containing the PDA or cell phone. It is usually very difficult to determine if the PDA or cell phone has suffered a fall. Sensors are normally used to determine whether the PDA or cell phone has suffered a fall or an external impact. There are a variety of sensors available, such as a capacitance sensor, a suspension spring sensor, a magnetic induction current sensor, a mass-acceleration sensor, a magnetoresistive sensor, a spring mass sensor, a piezoelectric sensor, and a fluid sensor.
U.S. Pat. No. 5,970,794 discloses a shock sensor utilizing a coil that produces a magnetic field. The magnetic field changes when there is a shock and the sensor outputs an induced electric current.
U.S. Pat. No. 5,983,724 discloses a shock sensor that contains a magnetic shock-sensing member rotatably disposed in the sensor. When there is shock, the magnetic shock-sensing member rotates and outputs a signal caused by a magnetoresistive effect.
U.S. Pat. No. 5,575,479 discloses a projectile impact indicating target. When the projectile is hit, an impact indicator is released from the projectile.
Taiwan Patent No. I 255342 discloses a shock sensor comprising a spring plate apparatus disposed inside a cell phone. The spring plate apparatus comprises two spring plates that are connected together and have electrical currents passing through. When the cell phone suffers a fall or an impact, one of the spring plates disconnects with the other and turns off the electrical current.
Shock Watch Company produces a shock indicator model no. MAG2000. The shock indicator is for placing on the container used for transporting products or machines. The indicator is basically a casing with two rooms. A magnet is placed in the center of one room, and a magnetic material is movably placed in another room. The impact direction and the magnetic field line generated between the magnet and the magnetic material are perpendicular. The magnetic material is attracted to the magnet, and when the indicator suffers a drop or an impact, the magnetic material moves towards the direction of the impact or fall; whether the container has suffered a fall or an impact can thus be determined.

Industrial Technology Research Institute


This disclosure is directed to techniques for controlling the execution speed of a processor that executes audio processing algorithms. In some examples, the execution speed of the processor may be controlled based on one or more delay parameters that are obtained from querying one or more tasks that execute the audio processing algorithms. The delay parameters that are returned by the tasks in response to the queries may, in some examples, be dependent upon one or more algorithm-specific parameters that are used to configure the audio processing algorithms. The techniques of this disclosure may be used to reduce the amount of power consumed by a processor that is configured to execute one or more audio processing algorithms in an audio communication device, which may be particularly useful in audio communication devices where power resources are limited, such as, e.g., a mobile phone.

Audio communication devices are used to provide one-way and/or two-way communication between two different devices over a communication channel. Audio communication devices may include devices such as, e.g., wireless communication devices, wired communication devices, voice communication devices, mobile telephones, mobile telephone handsets, mobile telephone headsets, Bluetooth devices, tablet personal computers, tablet phones, landline telephones, Internet telephones, personal digital assistants (PDAs), smartphones, etc.
In order to effectively transmit and receive audio data between two different devices and in order to improve the quality of the communication experience, an audio communication device may include one or more processors that are configured to process digital audio waveforms using one or more digital signal processing (DSP) algorithms. For real-time communication applications, the DSP algorithms may need to perform many calculations in a relatively short period of time. To ensure that there are sufficient processing resources to perform the number of calculations needed in the required amount of time, the one or more processors may need to be clocked at a relatively high rate, which may consume a significant amount of power.

Controlling the execution speed of a processor in an audio processing system


An alarm operation is activated by closing all vehicle doors (S11). When all doors are locked (S12), an active alarm awaiting state is set (S13) and, when all doors are not locked (S12), a passive alarm awaiting state is set (S16). When all the doors are locked after a passive alarm awaiting state was set (S17), the passive alarm awaiting state shifts to an active alarm awaiting state. Then, whether or not all doors are unlocked is judged (S14). If they are unlocked, the alarm awaiting state is released (S15). If the alarm mode is preserved intact, without shifting to be in an active alarm mode, the alarm awaiting state is released (S15) by turning on an ignition or accessory switch within fifteen seconds after a door was opened (S18).

1. Field of the Invention
The present invention relates to a vehicle theft prevention device which signals an alarm in response to a predetermined action performed to a vehicle when the device equipped to the vehicle is in an alarm awaiting state. In particular, an alarm awaiting state can be set and released in a plurality of modes in this device.
2. Description of the Related Art
Conventionally, many devices have been proposed to prevent vehicle thefts, including one which raises various alarms in response to unauthorized actions performed to the vehicle such as unauthorized opening of doors. For such vehicle theft prevention devices, authorized operations must be discriminated from unauthorized operations.
For such discrimination, two methods are known, an active alarm mode and a passive alarm mode. In the active alarm mode, an alarm awaiting state is set by locking all the doors after an ignition key was pulled out, and released by authorized unlocking the doors. If unauthorized operations are made to a vehicle while the device is set in an alarm awaiting state, the device signals an alarm. With this method, an alarm will be signaled if a door, etc., is forcibly opened when locked.
In the passive alarm mode, on the other hand, closing all the doors initiates an alarm awaiting state, and such a state is released by operating an ignition key within a predetermined period of time after a door was opened. If an ignition key is not operated within a predetermined period of time after a door was opened, an alarm will be raised. With this method, an alarm will be given if a door is opened by someone who does not have ignition key.
Note that the above devices are disclosed in U.S. Pat. No. 4,383,242.
In the active alarm mode, an alarm awaiting state is initiated by locking all the doors and released by unlocking them, as mentioned above. Because an authorized user having a key does not forcibly open the door, the active alarm mode is advantageous in that the discrimination can be highly accurate. However, it has such a problem that no alarm will be raised if any of the doors were left unlocked.
In the passive alarm mode, an alarm awaiting state is instantly set when the user simply exists the vehicle and closes the doors. However, an alarm may possibly be activated also in response to an operation by an authorized user. That is, if a user first closes all the doors and again opens a door to get something left inside, an alarm will be raised in a predetermined period of time.


An adjustable cam buckle assembly is described herein. The adjustable cam buckle assembly may include a cam buckle member, a retaining member and a clamp. The cam buckle member may include a hook section and a buckle section, wherein the buckle section may include a central opening and at least one slot. The retaining member may be engaged with the hook section, wherein the retaining member and the hook section may be capable of selectively securing a member within the hook section. The clamp may be pivotally engaged with the buckle section, wherein the clamp may be capable of engaging a strap within the buckle section.

Typically, various types of strap and buckle devices have been utilized for retaining items, such as tarps, in place over cargo or other objects to be protected against the elements. These devices may have generally incorporated a buckle through which a strap may be adjusted as to its length. The strap may be stitched to the tarp at one end or otherwise attached thereto. The buckle in many of these devices may have an attachment means connected to one end. For example, this attachment means may comprise a hook that may fit over the arm of a U-shaped anchoring bracket. These types of devices, however, may have several shortcomings.
For example, the hooks employed by many of these devices may readily become detached from the bracket should the tension on the strap loosen. This of course could result under various types of conditions, such as windy conditions, where movement is applied to the buckle. In addition, conventional cam buckles may employ complex tensioning means to both retain and release the strap for adjustability. These complex means often add cost to the device as well as complicate the process of adjusting the length of the strap.


A computer process interconnects logic circuit on an integrated circuit substrate by generating a single softwire statement for each interconnection, and by thereafter utilizing the softwire statements to generate multiple physical layouts for each interconnection. A "softwire statement" is a computer-generated statement which specifies and establishes a route for an interconnection from one terminal of a logic circuit to another terminal as a series of conductive segments which extend in certain directions between relative jog points that are referenced to blockages such as the logic circuits, on the substrate.

This invention relates to Computer Aided Design (CAD) systems; and more particularly, it relates to CAD software programs which lay out physical interconnections for logic circuits on an integrated circuit substrate.
As one example, the above logic circuits can be a variety of logic cells and the above substrate can be a single semiconductor chip. As another example, the logic circuits can be several integrated circuit chips and the substrate can be a multichip ceramic wafer. In a typical CAD system, a library of many different types of logic circuits is provided; and from that library, certain logic circuits are selected for placement on each particular substrate. Usually, a logic cell library contains over one hundred different types of cells such as various types of NAND gates, NOR gates, AND gates, OR gates, multiplexers, latches, flip-flops, etc.; and several thousand of such cells are usually placed on a single semiconductor chip.
Each logic circuit has one or more input terminals and one or more output terminals; and, those terminals need to be selectively interconnected on the substrate. A listing of which terminals are to be connected together is provided by a netlist. Given the netlist and the list of circuits that are selected from the library, the problem arises of precisely where on the substrate each of the selected circuits and each of the circuit interconnections should be physically located. As the number of circuits plus the number of interconnections increases, solving the above "layout" problem becomes more and more tedious.
Originally in the prior art, the above layout problem was solved as follows. To begin, a design engineer or technician assigned specific locations on the substrate to each of the logic circuits. This was done by defining a fixed x, y coordinate system on the substrate, and by giving specific x and y dimensional coordinates to each of the circuits. Thereafter, a CAD software program received as an input the x and y dimensional coordinates of each of the circuits along with the netlist; and as an output the CAD program provided specific x and y dimensional coordinates to each of the circuit interconnections. In performing this task, the CAD program performed a global routing step in which certain open channels were found for each interconnection, and it performed a detailed routing step in which specific x, y dimensional coordinates were assigned to each interconnection in its channel.
Later in the prior art, another CAD layout system called a symbolic layout CAD system was developed. With the symbolic layout CAD system, a design engineer or technician graphically locates the logic circuits by electronically arranging various symbols that represent those circuits on CRT screen. Typically, the symbols are moved on the CRT screen by means of an electromechanical "mouse". Also the design engineer/technician uses the mouse to draw lines on the CRT screen from one symbol to another, as a representation of physical conductors between the logic circuits. Then, after the desired arrangement of the symbols and lines is made, another CAD program called a "Compactor" assigns dimensional x and y coordinates to each of the circuits and conductors that correspond to symbols and lines.
A problem however, with both of the above described processes is that they are too inflexible to accommodate certain changes to the physical layout of the cells and their interconnections which inevitably need to be made multiple times during the design and checkout of any new project. For example, such a change is needed to correct each error in the design, and to accommodate each new functional requirement of the design, and to comply with each change in the layout rules. With the above CAD systems, each time the physical layout of the logic circuits on the substrate changes, all of the layout steps for the logic circuit interconnections need to be repeated; and, that costs both time and money.
Accordingly, a primary object of the invention is to provide a novel CAD process in which the logic circuits can be moved on the substrate and the layout of the interconnections can be obtained without repeating all of the layout steps from the scratch.

Computer process for interconnecting logic circuits utilizing softwire statements


External power supply system includes an electrical storage device, motor, inverter that drives the motor by using electric power of the electrical storage device, and a control device controls the inverter. The inverter includes a first and second switching elements connected in series with each other between a positive and negative electrode power supply lines. A connection-node of the first and second switching elements is connected to one corresponding stator coil. The control device inputs signals to the inverter to drive the inverter such that voltage at the neutral point becomes a predetermined value. The control device compensates for signals in dead time period, the period in which off-state signals are supplied to the first and second switching elements, on the basis of current that is input from the connection-node to one corresponding stator coil or output from one corresponding stator coil to the connection-node while an engine is driven.

1. Field of the Invention
The invention relates to an external power supply system and, more particularly, to an external power supply system configured to output electric power of an electrical storage device to an external device via an inverter.
2. Description of Related Art
Japanese Patent Application Publication No. 2010-098851 (JP 2010-098851 A) describes a hybrid vehicle configured to charge a battery with the use of an external power supply connected to neutral points of motor generators.
It is conceivable to supply electric power from the battery to a device outside the vehicle by utilizing the neutral points of the motor generators of the hybrid vehicle including the configuration as described in JP 2010-098851 A.
However, because there occurs an error in dead time period that is a period during which an off-state driving signal is supplied to both upper-arm and lower-arm switching elements of an inverter (hereinafter, such an error is termed dead time error), there also occurs an error in output of electric power from the neutral points. Particularly, there is a difference in dead time error between when an engine is driven and when the engine is not driven, so it is required to appropriately compensate for an inverter command value in dead time period when the engine is driven.


A diagnostic tool includes a sensor for capturing at least one biosignal produced by a patient's heart and a computer device that implements a neural network iteratively trained via machine learning to generate a prediction about a heart condition of the patient. After the neural network is trained, the computer device can convert the at least one biosignal to a multi-dimensional input matrix for the deep neural network generated from a number (N) of biosignals captured by the sensor. The computer device then processes the multi-dimensional input matrix through the deep neural network, which subsequently outputs the prediction about the heart condition of the patient.

Approximately seven million Americans undergo emergency cardiac triage each year and the length of time to reach a final coronary diseases diagnosis is 8 to 72 hours. Also, approximately 40% of patients receive unnecessary coronary catherization, and 55-85% patients are considered to be over treated. Despite these measures, 2-6% of sick patients are discharged without treatment. Nearly 4 million cardiac catheterizations are performed annually in United States hospitals alone, with one in ten discharges having undergone coronary arteriography. Of these procedures, it is found that over 60% of them find patients with non-obstructive coronary artery disease—which is surprising as this is an invasive test reserved for the highest risk patients. Tests to indicate coronary disease, and thus need for cardiac catheterization, are generally accurate to an average of about 85%; meaning patients are sent for invasive catheterization with significant uncertainty of the need for such procedure. The innovation presented herein increases this accuracy and therefore provides for better estimate of procedure need, and it does so within seconds, and for a fraction of the cost of the hours-long testing currently used.

Medical diagnostic tool with neural model trained through machine learning for predicting coronary disease from ECG signals


An alignment system and method for a wafer stage. A chopper is used. A wafer stage is disposed at one side of the chopper, while a detector is disposed at the other side of the chopper. The chopper is rotating with a constant angular frequency. The detector is to detect the wafer stage, while the wafer stage is covered by the blade of the chopper, the measured signal is zero, while the wafer stage is not covered by the bladed and is detected by the detector, a signal is obtained. Therefore, a duty cycle and a phase can be read from the detector. Thus, with a constant rotating angular frequency, an actual position of the measured object can be obtained to align the wafer stage.

1. Field of the Invention
The invention relates in general to a stepper and a method used for an alignment of positions of a wafer stage or a wafer on the wafer stage. More particularly, the invention relates to an alignment system and method using a chopper instead of an interferometer.
2. Description of the Related Art
In a semiconductor fabrication process, photolithography process plays an important role for further reduction of dimensions of devices and higher integration of more and more devices. In the photolithography process, whether the wafer stage or the wafer on the wafer stage is precisely aligned directly determined the precision of pattern, and thus, determines the quality of devices. In a currently widely used stepper, some sub-systems such as wafer stage, alignment system, illuminator and lens determine the performance of the stepper, and consequently, determine the properties and characteristics of the end products.
A typical stepper has a high speed stage that xe2x80x9cstepsxe2x80x9d the wafer precisely with respect to the imaging optics and the IC reticles (photomask), moving the distances necessary to exactly repeat the image field in a Cartesian grid and thus fill the wafer surface. In the typical reduction stepper the stage travels in the horizontal plane underneath a fixed, vertically mounted lens. Once the wafer is placed on the exposure chuck and stepped under the lens, it is aligned by automatic systems that detect wafer targets optically and move the stage in small increments to correct the wafer position with respect to the ideal image field. The wafer is also positioned in vertical axis by autofocus systems, which in modern steppers also include the capability to pivot the vacuum chuck that holds the wafer during exposure in order to reduce any net tilt in the wafer surface due to chuck or wafer flatness errors.
FIG. 1 shows a conventional technique that employing heterodyne Interferometer to measure the position of the wafer stage. A laser beam emitted from a laser light source 102 reaches a beam splitter 108. Ideally, half portion of the laser beam passes through the beam splitter 108, while the other half portion of the laser beam is reflected to a reference mirror 106. These two beams then merge onto a detector 104. The combination of these two beams is either a result of constructive interference or a destructive interference, depending on the phase of the beams. The intensity of the signal detected by the detector 104 reflects the position of the wafer stage 100. The shifting direction of the wafer stage 100 can be obtained from the light reflected by the stage mirror according to the theory of Doppler Shift.
In addition, by installing one heterodyne interferometer at each direction such as X-axis, Y-axis and Z-axis can thus measure the displacement or rotation of the stage.
In the above conventional design of alignment system for wafer stage, the precision of the interferometers is prominently affected by vibration, stability of light source and fluctuation of power source. Especially for scanning the photomask and wafer, the control of vibration is the major factor to determine the throughput of the stepper.
The invention provides an alignment system for a wafer stage. A chopper is placed between the wafer stage and a detector. The wafer stage is placed within the scanning coverage of the chopper, while the detector measures a duty cycle and a phase of observation of the object at the other side of the chopper. According to the measured duty cycle, whether the wafer stage is aligned can be determined. This alignment system is not affected by vibration and the stability of light source or power source. Therefore, even the vibration of the wafer stage or the system is serious or the light source or power source is unstable, the position of wafer stage can be precisely corrected.
Thus, by employing the alignment system mentioned above, a method of precisely aligning a wafer stage is further provided. A wafer stage which may include an alignment mark thereon is provided. A chopper is placed on top of the wafer stage, or more specifically, on top of the alignment mark on the wafer stage, while the wafer stage of the alignment or object on the wafer stage to be aligned is within coverage of the chopper. The chopper is rotating with a constant speed, while a detector is disposed behind the chopper. The duty cycle and the phase for observing the wafer stage in front of the chopper are read by the detector. While the duty cycle and phase read from the detector are not consistent with a predetermined duty cycle when the wafer stage is precisely aligned, according to the difference of the duty cycle and phase, the exact positions of the wafer stage can be obtained.
Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.


A method is provided for tribological lubrication of sliding contact surfaces, where two surfaces are in contact and in motion relative to each other, operating in a vapor-phase environment containing at least one alcohol compound at a concentration sufficiently high to provide one monolayer of coverage on at least one of the surfaces, where the alcohol compound continuously reacts at the surface to provide lubrication.

The present invention relates generally to a method of lubricating contacting, sliding surfaces and, more particularly, to lubricating contacting and rubbing surfaces exemplified in microelectromechanical (MEMS) systems using a vapor-phase operating environment.
Commercially successful MEMS devices to date have either nonmoving parts or contacts whose lateral motion is very restricted. Many more exciting applications can be attained with MEMS devices consisting of moving, touching, and rubbing structures. These include gears and motors that can enable much more complicated mechanical functions at the micro- and nano-scale. However, the effects of adhesion, friction and wear of MEMS devices are challenging the development and commercialization of more sophisticated micromachines.
The tribological behavior of contacts in MEMS technologies differs from those in macroscopic engineering structures. At the macroscopic scale, millions of asperities give rise to the parametric relationships that we are familiar with, such as Amanton's law which depicts the friction coefficient to be independent of contact area and applied load. In MEMS, real mechanical contacts typically consist of a few nanometer-scale asperities that touch. At these small scales, Amonton's law breaks down and individual asperity contact behavior must be considered. Additionally, forces that are negligible at the macro-scale become significant at the microscopic length scale and smaller. These include electrostatic or van der Waals forces between contacting and non-contacting surfaces, and capillary forces due to liquid menisci. In the macroscopic scale, gravity dominates over adhesion. However, in the micro- and nano-scale, gravitational and inertial forces are negligible and adhesion becomes significant. It is important to point out that in some cases the magnitude of these forces is comparable to the actuation forces that can be provided with on-chip actuators.
Adhesion, friction and wear have been the greatest limitations to the development of MEMS devices that rely on contacting and rubbing surfaces. These tribological problems associated with micromachines cannot be solved by applying conventional lubricants utilized in the macro-scale, such as liquid lubricants. In micromachines, the viscosity of liquid lubricants causes severe power dissipation problems and causes devices to move slowly, negating one of the principal advantages of micromachines, i.e. low inertia that enables rapid mechanical switching.
Coupling agents having a functional end that can bond with the surface and a low energy end group pointing toward the free surface have been very successful as processing aides. These coatings can be applied from the liquid phase immediately after removal of the sacrificial layer to prevent adhesion as liquid dries from the part, or from the vapor phase once the liquid remaining after the release etch is supercritically extracted. In either case, the coupling agents form a chemisorbed monolayer of organic molecules that is ideally densely packed on the surface, so that the low energy end groups cover the entire surface. These surfaces are hydrophobic and resist the adsorption of water as well as organic contaminants much better than uncoated devices do. These types of coatings have been critical to having operating devices survive packaging operations and remain functional. However, it is well recognized that since these coatings are chemically bound to the surface and only a monolayer thick, that once they are displaced by wear or reaction with atmospheric species they leave the surface unprotected. Work over the last decade with various MEMS structures having sliding surfaces has shown that chemisorbed monolayers alone are insufficient to allow long operating life. Long-life MEMS devices with sliding surfaces will require a system for replenishing the lubricating layer as the device operates.
No commercial MEMS devices with repetitive sliding contacts exist today. MEMS devices are typically fabricated with silicon-based materials because mature lithographic fabrication techniques are available from the semiconductor industry; however, silicon and its native oxide exhibit high friction and poor wear resistance in sliding contacts. To overcome these problems, various coatings have been developed and extensively studied, but with questionable reliability and feasibility. Thin protective coatings are subject to wear during operation, limiting device lifetime. A means of continuously replenishing the protective layer on these surfaces is required to overcome this limitation. An additional requirement is that the lubricant must be deposited conformal to the surfaces, not possible with typical physical vapor deposition (PVD) techniques which deposit via line-of-site or chemical vapor deposition (CVD) techniques which deposit non-uniformly and do not easily coat buried surfaces. In vapor-phase lubrication (VPL), the adsorption of gas-phase molecules on device surfaces can produce a conformal lubricant layer. During sliding contact, adsorbed molecules can be desorbed from the surface; however, as long as the vapor pressure of lubricating molecules is maintained, these molecules immediately re-adsorb and replenish the lubricant film. Adsorbed films have been used to repassivate dynamic digital mirror arrays; but this device does not have deliberate sliding contacts. Previous VPL required elevated temperatures and lubricant molecule activation via precursor catalytic metal coatings. Useful would be a vapor-phase lubrication strategy that works in ambient conditions without special coatings.

Method for lubricating contacting surfaces


A product is on a surface provided with a first position code which codes coordinates for a plurality of first points. In at least one partial area on the surface, the product is further provided with a second position code which codes coordinates for a plurality of second points. The partial area further comprises a field which is associated with a predetermined function to be performed in consequence of a user unit being placed in the field. Methods and devices for coding and for recording of information from a surface are also described.

It is already known that it is possible to digitize handwriting by determining how a pen used to create the handwriting is moved. One way of doing this is to use a base for the handwriting provided with a position-coding pattern which codes coordinates for points on the base, and also to provide the pen with a sensor which records the position-coding pattern locally at the tip of the pen as the pen is moved across the base. A processing unit, which can be placed in the pen or at a distance therefrom, can then decode the recorded position-coding pattern so that the movement of the pen across the base can be determined as a series of coordinates.
WO 01/26032, which is assigned to the applicant of the present application, describes a position-coding pattern which can be used precisely for digitizing handwriting. The pattern is made up of marks, which for example can be in the form of dots. Each dot has a nominal position represented by an intersection between two lines in a virtual raster, for example a square grid. Each dot codes a fixed value depending on its location in relation to the nominal position. The dots can have four possible locations, for example, one on each of the four raster lines extending from the intersection, the four different locations coding four different values. The coordinates of a point are coded with the aid of a plurality of dots, for example 6*6 dots. However, each dot contributes to the coding of the coordinates of a plurality of points. If a sensor first reads 6×6 dots and is thereafter moved one dot distance to the side or vertically, the sensor will read dots which code the coordinates of a new point. This type of pattern in which the position resolution is smaller than the size of the partial surface required for determining a position is in the present application referred to as "floating".
Using the position-coding pattern in the above-mentioned WO 01/26032, coordinates for a very large number of points can be coded, theoretically 436 points if each point is coded with 6*6 dots. All these points can be said to form an imaginary surface or form dots in a coordinate system.
WO 01/48685, which is also assigned to the applicant of the present invention, describes how such an imaginary surface can be used for information management. More specifically, different partial areas on the imaginary surface are dedicated to different types of information management. It is then possible to control how information which is recorded digitally is to be handled by providing bases with a position-coding pattern which corresponds to different partial areas on the imaginary surface. For example, a first base can be provided with a position-coding pattern which means that information which is written on the position-coding pattern and is recorded digitally by the pen is sent to a predetermined computer for storage in the latter. Correspondingly, another base can be provided with a position-coding pattern which means that information which is recorded digitally with the aid of this position-coding pattern is sent as an e-mail to an address indicated by the user on the base.
WO 01/48685 also describes how the pen which records the position-coding pattern can store different digital templates, which define how the information from different parts of physical bases with position-coding patterns is to be interpreted. An e-mail template can, for example, specify that a base with a corresponding position-coding pattern has a first field which is intended for a message, a second field which is intended for an e mail address to be interpreted by ICR (Intelligent Character Recognition), and a third field which constitutes a send box which the user ticks in order to initiate the sending of a recorded message.
Different bases can have fields with different functions. The number of fields can be different on different bases. The fields can further be located in different places on the bases, which besides may be of different sizes.
As is also described in WO 01/48685, the position-coding pattern can be arranged differently on the physical base. According to a first alternative, the position-coding pattern on the base can be continuous, which means that it corresponds to a continuous area of the imaginary surface. The processing unit which is to interpret and process the digital information recorded from the base must then know the layout of the base, i.e. which fields there are on the base and where these are located. If many different layouts are allowed, which is of course desirable, many different digital templates must be stored so as to be accessible to the processing unit. This is particularly a problem if the processing unit has a limited storage capacity and/or if it takes a long time to change the information once it has in fact been stored. This may be the case, for example, if the processing unit is arranged in a portable user unit, such as the pen in WO 01/48685.
According to a second alternative, the position-coding pattern on the base can correspond to a combination of a plurality of separate partial areas on the imaginary surface so that the position-coding pattern on the base will be discontinuous. In the above example the first field can then correspond to, for instance, a first partial area on the imaginary surface which is dedicated to message information, the position-coding pattern in the second field can correspond to a second partial area which is dedicated to address information which is to be processed by ICR, and the position-coding pattern in the third field can correspond to a third partial area which is dedicated to send boxes. In this case, the location of the fields on the base is thus not related to the location of corresponding partial areas on the imaginary surface. In this alternative, the unit which is to interpret and process the digital information from the base has to store a smaller quantity of information because it only needs to know the coordinates of the different partial areas on the imaginary surface.
In certain situations, however, a continuous position-coding pattern on the base is still to be preferred. If the pattern is of the floating type, positions will not be able to be defined in a boundary area between two different fields in the discontinuous position-coding pattern since the dots in the boundary area do not code coordinates for adjacent points on the imaginary surface. One way of solving this problem is to have no position-coding pattern in the boundary area so that points belonging to one or the other field can be detected unambiguously. Such boundary areas without position-coding pattern can be undesirable, especially when the product is small.
A further problem with a discontinuous position-coding pattern on the base may arise if the sensor in the pen is displaced from a pen point of the pen used to make graphical notes on the physical base. It may then happen that the pen point is placed in a first field in the discontinuous position-coding pattern, but that the sensor, owing to the displacement, records the position-coding pattern in another field on the base, which in turn may result in the pen not performing the function intended by the user.
The position-coding pattern corresponding to a digital template can be applied as it is on a base. Alternatively, different partial areas of the position-coding pattern corresponding to the digital template can be "cut out" and arranged in a different spatial arrangement on the base. The different partial areas of the digital templates correspond to different fields, which may have different functions, on the base.
The pen does not need to know the spatial arrangement of the different fields on the base in order to determine how to handle coordinates recorded from the base. However, if the movement of the pen over the base is to be displayed by an external unit, e.g. a PC, to which the coordinates are sent, the PC needs to know the spatial arrangement of the fields on the base. Unfortunately, the PC cannot determine the spatial arrangement from the coordinates sent to it from the pen.


A method for improving safety for use with a navigation GPS map system that can display the current location of a vehicle that contains the navigation system on a map generated by the system, the method warning of an approaching point of interest selected from a traffic light, a school zone, or a railway crossing that the vehicle is approaching by displaying an icon of the traffic light, school zone or railway crossing. The display can be limited to when a wireless communication device in the vehicle is in an active voice mode.

Talking on a phone while driving, whether with a hand-held phone or using an in-dash phone, is a major and dangerous distraction, to the point that a number of states have passed laws making it a misdemeanor to use of a hand-held phone while driving. A significant solution can be found U.S. Pat. Nos. 7,308,247 and 7,986,934, each tilted "Cellular Telephone Safety System" and which describe detecting when a traffic signal is near when a wireless communication device is in use and issuing an alarm, and which can be used to warn that the traffic light is red or is calculated to be red by the time the vehicle reaches the intersection. Such a system can also be used to generate a warning when the vehicle is approaching a school zone or a railway crossing. The teachings of U.S. Pat. Nos. 7,308,247 and 7,986,934, and the references cited therein are incorporated by reference herein. Vehicle GPS navigation systems and mobile GPS navigation systems display the location of the user on a map generated by the system. Such systems are capable of displaying icons showing locations on the map of various points of interest chosen by the user, such as ATMs, restaurants, fire stations, police stations, emergency rooms, and the like.

Safe driving system generating map points


Upon occurrence of a memory error which is difficult to correct, CPU interrupts a process under execution in response to interrupt signal output from error detection device, and transfers the control to the OS. The OS references attributes of a page stored in a page frame which has suffered the memory error. When read-only is indicated, physical memory management table is updated to set the page frame, which has suffered the error, into a disabled state. Then, page table is updated such that a virtual page stored in the page frame which has suffered the error is not assigned to any page frame, followed by resumption of the execution of the process. After execution of the process is resumed, a page fault process is invoked to store the virtual page which has encountered the memory error in another normal page frame.

An example of a memory failure recovery method in an information processing apparatus is described in JP-2000-132462A (hereinafter called "Document 1"). In the following, the memory failure recovery method described in Document 1 will be described with reference to FIGS. 1 and 2.
Referring to FIG. 1, the information processing apparatus described in Document 1 comprises CPU 101, main storage device 102, error detection device (ECC) 103, service processor 104, storage device (ROM) 105 for the service processor, auxiliary storage device 109, and data bus 108 which interconnects these components.
In the information processing apparatus having such a configuration, when an error occurs in a program area of main storage device 102 while the system is operating, a process shown in FIG. 2 is executed. First, error detection device 103 detects the occurrence of the memory error, and confirms the contents of the memory error (S101). A circuit called ECC (Error Check and Correct) is used in error detection device 103. ECC is an error detection and correction circuit which can detect that an erroneous value is recorded in a memory and corrects the erroneous value to a correct value. While a normal ECC is capable of correcting only one bit of error, some other types of ECCs are capable of correcting two bits or multiple bits of error. In Document 1, a normal ECC (capabilities to correct only one bit) is used. When a one-bit error is detected (NO at S102), an error correction is performed by the ECC (S103), followed by termination of the process.
When the error extends over two bits or more, error detection device 103 generates interrupt signals 106, 107 to CPU 101 and service processor 104 to temporarily halt CPU 101 (S104) or to request service processor 104 to execute a recovery process. Service processor 104 acquires data at an address at which the memory error has occurred and data at the address preceding thereto, from a backup file which resides within auxiliary storage device 109 (S105), and writes these data into a recovery area on main storage device 102 (S106). Next, service processor 104 writes a branch instruction into the address immediately before the memory address at which the error has occurred for branching to the data written into the recovery area, and writes a branch instruction immediately after the data written into the recovery area for branching to the address next to the address at which the memory error has occurred in main storage device 102 (S107). Then, service processor 104 changes the value of a program counter to the address immediately before the address at which the memory error has occurred (the address at which the branch instruction has been written) (S108), and releases the temporary halt instruction for CPU 101 (S109).
As CPU 101 resumes its execution, the branch instruction is executed at the address which has been set immediately before the address at which the memory error has occurred, causing CPU 101 to execute a program with those backup data written into the recovery area instead of the data at the address at which the memory error has occurred and data at the address preceding thereto in main storage device 102, and subsequently branch to the data immediately after the address at which the memory error has occurred in main storage device 102. In this way, a program can be continuously executed even if main storage device 102 suffers a memory error which is difficult to correct.

Memory failure recovery method, information processing apparatus, and program


An air-fuel ratio of each cylinder is estimated on the basis of a detection value of an air-fuel ratio sensor disposed in an exhaust confluent portion. An air-fuel ratio correction quantity is computed on the basis of the estimated air-fuel ratio of each cylinder. The air-fuel ratio of an air-fuel mixture to be supplied to each cylinder is corrected on the basis of the cylinder air-fuel ratio correction quantity to reduce a variation in the air-fuel ratio between the cylinders. When a state in which the cylinder air-fuel ratio correction quantity or its learning value of any cylinder is outside a specified range continues for a while during a period in which this cylinder air-fuel ratio control is performed, a combustion is stopped for the cylinder outside the specified range and the cylinder air-fuel ratio control is continuously performed only for other normal cylinders.

JP-A-2005-207405 (U.S. Pat. No. 7,051,725 B2) shows a cylinder air-fuel ratio control system including the controller. In this system, air-fuel ratios of a plurality of cylinders are estimated for the respective cylinders on the basis of the output of one air-fuel ratio sensor disposed in an exhaust confluent portion where exhaust gas from the plurality of cylinders joins, air-fuel ratio correction quantities of the respective cylinders (cylinder air-fuel ratio correction quantities) for correcting variations in an air-fuel ratio between the cylinders are computed for the respective cylinders, the cylinder air-fuel ratio correction quantities are learned by smoothing processing or the like, and cylinder air-fuel ratio control for controlling the air-fuel ratios (fuel injection quantities) of the plurality of cylinders for the respective cylinders is performed on the basis of the cylinder air-fuel ratio correction quantities and their learning values. Further, in this cylinder air-fuel ratio control system, on operating condition that the estimation of the cylinder air-fuel ratio is difficult (the computation of the cylinder air-fuel ratio is difficult), the cylinder air-fuel ratio control is performed by the use of the learning values of the cylinder air-fuel ratio correction quantities.
In this cylinder air-fuel ratio control system, there may be a case where, for example, if the fuel injection valve or the like of any cylinder becomes abnormal and the control of the air-fuel ratio of the cylinder becomes difficult, variations in the air-fuel ratio between the cylinders becomes abnormally large and the cylinder air-fuel ratio correction quantity and its learning value become abnormally large. Even if the cylinder air-fuel ratio control is continuously performed in this state, variations in the air fuel ratio between the cylinders cannot be reduced, which results in excessively correcting the air fuel ratio of the normal cylinders other than the abnormal cylinder and hence raises a problem that exhaust emission deteriorates.
Moreover, in the foregoing cylinder air-fuel ratio control system, there may be a case where when the air-fuel ratio control becomes difficult for any cylinder because of the failure of the fuel injection valve or the like, the air-fuel ratio of the abnormal cylinder for which the air-fuel ratio control becomes difficult is greatly varied in a lean direction. As a result, the air-fuel ratio of exhaust gas flowing into a catalyst (in other words, exhaust gas of a mixture of exhaust gas of the abnormal cylinder and exhaust gas of the normal cylinders) can be shifted in the lean direction. If the air-fuel ratio of exhaust gas flowing into the catalyst is shifted in the lean direction, the quantity of lean component (oxygen quantity) flowing into the catalyst is increased to accelerate oxidation reaction of rich components such as HC and CO to raise a possibility that the catalyst may be overheated and failed by the reaction heat.
Moreover, to prevent a catalyst for cleaning the exhaust gas of an internal combustion engine from being failed by overheat, there is proposed an apparatus as described in JP-A-56-20727 which controls an air-fuel ratio in a direction to decrease the temperature of the catalyst when the catalyst is determined to be overheated.
When the catalyst is determined to be overheated, if the air-fuel ratio of each cylinder is controlled by the use of this apparatus in a direction to decrease the temperature of the catalyst, there are raised the following problems: because the air-fuel ratio of the abnormal cylinder for which the air-fuel ratio control is difficult cannot be controlled with high accuracy in the direction to decrease the temperature of the catalyst, it is difficult to control the air-fuel ratio of exhaust gas (in other words, exhaust gas of a mixture of exhaust gas of the abnormal cylinder and exhaust gas of normal cylinders) with high accuracy in a direction to decrease the temperature of the catalyst; and because the air-fuel ratio of each cylinder is controlled in the direction to decrease the temperature of the catalyst after the catalyst is determined to be overheated, it is impossible to prevent the catalyst from being overheated before the catalyst is overheated.

Cylinder air-fuel ratio controller for internal combustion engine


A standard diesel injection system and a mechanical direct-gas injection system are selectively operable, in combination with a continuous pilot injection system, to provide a combustion system that is capable of operating in either a conventional diesel mode or a dual-fuel mode. Operation between convention diesel or dual-fuel combustion modes is mechanically controlled by a two-position, four-way control valve. The mechanical direct-gas injection system is actuated by pulsed diesel fuel directed to the actuation chamber of a gas injector by the same injection pump used to provide diesel fuel to the combustion chamber during conventional diesel operation.

1. Technical Field
The present invention is directed to a system and method for operating a diesel engine in both conventional diesel and dual fuel operating modes, and more particularly to such a system and method in which a pulsed flow of diesel fuel is continuously introduced into the combustion chamber of the engine through a pilot injector during operation in both operating modes.
2. History of Related Art
Increasing concern over exhaust emissions regulation and fuel efficiency have led to an interest in burning a combustible gaseous mixture, such as propane or natural gas in diesel engines, particularly in diesel engines used in stationary, marine, and locomotive applications. Many of these applications use dual fuel combustion systems due to the requirement that diesel operation capability be retained, due to either limited refueling infrastructure, intermittent operation, or limited on-board fuel storage capability. Current dual fuel combustion systems are either homogeneous or heterogeneous gas-air charge systems, and each have distinct advantages and disadvantages.
Homogeneous charge duel fuel combustion systems typically require a reduction in compression ratio and/or a reduction in inlet air temperature to avoid undesirable early detonation of the gas-air charge. This problem is discussed in a Non-Petroleum Vehicular Fuels III Symposium paper The Diesel-Gas Dual-Fuel Engine, by G. B. O'Neal, Published by the Institute of Gas Technology, 1982. Natural gas composition and mixing of the gas-air charge are concerns with homogeneous charge dual-fuel systems, as they greatly affect the potential for detonation and combustion rate. Generally, either some form of load control, i.e., throttling or waste gate, is required for starting and/or light-load operation, or the engine operates on undiluted diesel fuel under those conditions. Such a dual fuel engine is described in an article titled The Dual Fuel Engine by G. A. Karim, appearing in Automotive Engine Alternatives, Robert L. Evans editor, Plenum Press, New York, 1987. Although diesel efficiency can be matched and significant reductions in oxides of nitrogen (NO.sub.x) emissions are obtained when operating in a homogeneous dual-fuel mode at rated conditions, the engine modifications required for dual-fuel operation cause substantial loss in efficiency when operating at reduced load or on 100% diesel fuel. Also, increased cold start and light load emissions occur, along with reduced efficiency, if the engine is unthrottled and operates on 100% diesel fuel at reduced compression ratios.
Heterogeneous, i.e., stratified, charge dual-fuel combustion systems typically feature direct injection of natural gas late in the compression cycle. By injecting natural gas at high pressure late in the cycle, premature detonation is avoided and no modifications to the inlet air and compression chamber are required. This operation is described in SAE Paper No. 872041, titled High-Pressure Late Cycle Direct Injection of Natural Gas in a Rail Medium Speed Diesel Engine, authored by J. F. Wakenell, G. D. O'Neal, and Q. A. Baker. Normal diesel operation is retained in the described engine operation without penalties in emissions or efficiency. In the dual-fuel operation mode, natural gas is stratified within the combustion chamber and burned in a manner similar to the diesel cycle. The dual-fuel efficiency is typically equivalent to, or better than, that of 100% diesel operation and NO.sub.x and particulate matter emissions are significantly reduced from typical diesel operating levels. Although the heterogeneous dual-fuel NO.sub.x and particulate emission reductions are less than homogeneous dual-fuel system levels, the improved efficiency at all operating conditions and reduced light-load emissions present a better trade-off in many applications.
While heterogeneous dual-fuel systems present many benefits over homogeneous systems, the expense and complexity of high pressure, direct-gas injection systems are prohibitive for many applications. Current direct gas injectors are electronically controlled and hydraulically or pneumatically actuated, requiring additional electronic controls and hydraulic or pneumatic systems for operation. Older, mechanical direct injection systems are much less flexible in control capability, and typically feature cam-actuated poppet valves that require significant additional components for actuation and control, and typically operate at much lower pressure.
The present invention is directed to overcoming the problems set forth above. It is desirable to have a simple, manually selectable combustion system capable of operating in either a diesel or a dual-fuel combustion mode. It is also desirable to have such a combustion system that is applicable to two-and/or four-stroke diesel engines and, desirably, may be easily retrofitted to existing diesel engines or readily applied to new dual-fuel engines. It is further desirable to have such a combustion system that uses a continuous duty pilot injection system to provide an ignition source for dual-fuel operation, and improved exhaust emissions when operating in the neat, or 100%, diesel combustion mode.

System and method for a dual fuel, direct injection combustion engine