A tape carrier of the present invention includes an insulating tape and a wiring pattern formed on the insulating tape. The wiring pattern includes a connecting section via which the wiring pattern is connected to a bump electrode. The connecting section is provided at a part of an overlap part of the wiring pattern, which overlap part overlaps a semiconductor device when the semiconductor device is mounted on the wiring pattern. The connecting section of the wiring pattern is smaller in wiring width than the remaining part of the overlap part, which remaining part is other than the connecting section.

TCP (Tape Carrier Package) type semiconductor apparatuses (hereinafter, "TCP semiconductor apparatus") have conventionally been known as semiconductor apparatuses in which a semiconductor device is mounted on and coupled to a flexible printed circuit.
In recent years, COF type semiconductor apparatuses (hereinafter, "COF semiconductor apparatus) have been employed. In the COF semiconductor apparatus, a semiconductor device is mounted on and coupled to a flexible printed circuit by use of the COF method.
The following are exemplary differences between the TCP semiconductor apparatuses and the COF semiconductor apparatuses.
(i) In the TCP semiconductor apparatus, an opening section is made in advance in an insulating tape used as a base substrate of a flexible printed circuit. The opening section is utilized to mount a semiconductor device. A wiring pattern is formed in the opening section so as to protrude in the shape of a cantilever. A top end section of the wiring pattern is coupled to the semiconductor device. On the other hand, in the COF semiconductor apparatus, a thin film of an insulating tape, which is used as a base substrate in a flexible printed circuit, has no opening section to be utilized to mount a semiconductor device. The semiconductor device is mounted on and coupled to a wiring pattern formed on a front surface of the thin film of the insulating tape.
(ii) In the TCP semiconductor apparatus, the wiring pattern protrudes in the shape of a cantilever. This makes it difficult to produce a wiring pattern with a wiring pitch smaller than 45 μm. On the other hand, in the COF semiconductor apparatus, the wiring pattern is formed on the front surface of the thin film of the insulating tape. It is therefore easy to produce a wiring pattern with a wiring pitch of 35 μm or smaller.
(iii) The TCP semiconductor apparatus includes a slit along which the TCP semiconductor apparatus is to be folded after being mounted on a liquid crystal panel or the like. On the other hand, the COF semiconductor apparatus has no such slit. The COF semiconductor apparatus can be folded along any line of the thin film of the insulating tape.
(iv) The TCP semiconductor apparatus is produced by adhering, with a bonding agent, a copper foil to an insulating tape made of polyimide. On the other hand, the COF semiconductor apparatus is produced by applying polyimide or the like to a rear surface of a copper foil and then carrying out hardening to form the shape (casting). Alternatively, the COF semiconductor apparatus is produced by carrying out sputtering to form a layer of copper on the thin film of an insulating tape made of polyimide or the like (sputtering, metalizing).
As described above, in view of purposes of use, the COF semiconductor apparatus employs, as the base substrate in the flexible printed circuit, the thin film of the insulating tape that can be folded freely. Respective wirings of the wiring pattern provided on the front surface of the thin film of the insulating tape are electrically connected to corresponding terminals of the semiconductor device. A connector section for external connection is connected to a liquid crystal panel, a printed wiring board, and the like. Solder resist is applied to the remaining revealed part of the wiring pattern other than those mentioned above, thereby keeping the remaining revealed part insulated.
It is easier with the COF semiconductor apparatus to realize a finer pitch of the wiring pattern (inner lead) than with the TCP semiconductor apparatus. A lower limit of the wiring pitch in mass-produced TCP semiconductor apparatuses is 45 μm. On the other hand, mass production of COF semiconductor apparatuses with the wiring pitch of 35 μm has been carried out. With the COF semiconductor apparatuses, it is possible to realize a wiring pitch of 30 μm or smaller.
The COF semiconductor apparatuses have been demanded to be responsive to multi-pins, and at the same time, to become smaller and thinner. To meet the demands, the following are necessary. First, a pitch of the sections connecting the wiring patterns and the semiconductor devices needs to be finer. Further, a pitch of the connector sections of the wiring pattern for external connection needs to be finer. Furthermore, insulating tapes, wiring patterns, and the like need to be thinner. To make the pitches of the wiring patterns (inner lead) finer, the width and the thickness of the wiring patterns (inner lead) need to be reduced.
FIGS. 5 and 6 each show a schematic structure of the vicinity of a mount section (mount area) of a semiconductor device in a conventional general COF semiconductor apparatus. FIG. 5 shows a case in which the wiring pitch of the wiring pattern is 35 μm or greater. FIG. 6 shows a case in which the wiring pitch of the wiring pattern is smaller than 35 μm (in this case, the wiring pitch is finer than that in the case shown in FIG. 5). Hereinafter, the conventional case shown in FIG. 5 will be referred to as "conventional apparatus 1", and the conventional case shown in FIG. 6 will be referred to as "conventional apparatus 2".
As shown in FIGS. 5 and 6, the wiring pattern 23 in a flexible printed circuit for a conventional general COF semiconductor apparatus is formed in such a manner that a part of the wiring pattern 23, which part is indicated by the dashed double-dotted lines in FIGS. 5 and 6 and is to be connected to the bump electrode 25 of the semiconductor device 24, and the remaining part of the wiring pattern 23 have a same width (wiring width).
On the other hand, Patent Document 1 (U.S. Pat. No. 3,536,023; Date of Registration: Mar. 19, 2004; Date of Issue: Jun. 7, 2004) describes a known technique in which a width of a wiring pattern is partially changed. FIG. 7 shows a schematic structure of the vicinity of a mount section (mount area) of a semiconductor device in the COF semiconductor apparatus (hereinafter, "conventional apparatus 3") disclosed in Patent Document 1.
As shown in FIG. 7, in the conventional apparatus 3, the wiring pattern 23 is formed so as to have a wide width in the vicinity of an edge of the opening section 22a of the solder resist 22. The wiring pattern 23 has the same width throughout the overlap part (i.e. part on which the semiconductor device 24 is to be mounted), which is indicated by the dashed double-dotted line and overlaps the semiconductor device 24, including a part to be connected to the bump electrode 25 of the semiconductor device 24 and the remaining part of the wiring pattern 23.
As mentioned above, there have been demands for COF semiconductor apparatuses with wiring patterns having finer pitches, thinner films of insulating tapes, and thinner films of wiring patterns. There are, however, several obstacles in realizing finer pitches and thinner films.
One of the obstacles is that, because the pitch of the wiring pattern (inner lead) is small, a defect occurs if the bump electrode of the semiconductor device is displaced when bonded to the wiring pattern (inner lead). Specifically, the wiring pattern (inner lead) comes into contact with an adjacent bump electrode to the bump electrode.
In other words, in a COF semiconductor apparatus with a fine wiring pitch smaller than 35 μm, if the bump electrode of the semiconductor device is displaced when bonded to the wiring pattern, the defect is likely to occur that the wiring pattern (inner lead) comes into contact with an adjacent bump electrode to the bump electrode. This problem is more likely to occur in a COF semiconductor apparatus with a wiring pitch of 30 μm or smaller.
One way to overcome the obstacles is to narrow the wiring pattern (inner lead). This prevents the defect even if the bump electrode of the semiconductor device is displaced when bonded to the wiring pattern. Specifically, the wiring pattern is prevented from coming into contact with an adjacent bump electrode to the bump electrode. However, narrowing the width of the wiring pattern (inner lead) results in degrading mechanical strength of the wiring pattern and bond strength between the wiring pattern and the insulating tape. This causes a problem that the wiring pattern is easily disconnected or easily peels off in the steps from mounting and bonding the semiconductor device to packaging the COF semiconductor apparatus into a module.
The COF semiconductor apparatus can be folded freely. There is, however, difficulty in realizing a finer pitch while maintaining this characteristic of the COF semiconductor apparatus, that is, the COF semiconductor apparatus can be folded freely. Specifically, folding the COF semiconductor apparatus freely causes the wiring pattern to be easily disconnected or to peel off easily. Therefore, the wiring pattern (inner lead) having been made finer needs to improve in mechanical strength and bond strength.
The following describes the foregoing obstacles, with reference to the conventional apparatus 1 and the conventional apparatus 2.
FIG. 8 schematically shows a structure of the connecting section, via which the semiconductor device 24 is connected to the wiring pattern 23, in the COF semiconductor apparatus shown in FIG. 5 (conventional apparatus 1), in the case in which the bump electrode 25 of the semiconductor device 24 is displaced when bonded to the wiring pattern 23. FIG. 9 schematically shows a structure of the connecting section, via which the semiconductor device 24 is connected to the wiring pattern 23, in the COF semiconductor apparatus (conventional apparatus 2) shown in FIG. 6, in the case in which the bump electrode 25 of the semiconductor device 24 is displaced when bonded to the wiring pattern 23. FIG. 8 shows a structure in part B shown in FIG. 5. FIG. 9 shows a structure in part C shown in FIG. 6.
As shown in FIG. 8, the wiring pitch is wide in the conventional apparatus 1. Therefore, even if the bump electrode 25 is displaced when bonded to the wiring pattern 23, the defect is less likely to occur that the wiring pattern 23 comes into contact with an adjacent bump electrode to the bump electrode 25. Thus, even if the bump electrode 25 is displaced when bonded to the wiring pattern 23, the wiring pattern 23 and the bump electrode 25 are electrically connected in a suitable manner.
With the conventional apparatus 2, the defect is more likely to occur. Specifically, if the bump electrode 25 is displaced when bonded to the wiring pattern 23, the wiring pattern 23 comes into contact with an adjacent bump electrode 25 to the bump electrode 25, as shown in FIG. 6.
As described above, one way to overcome the defect mentioned above is to reduce the width of the wiring pattern 23 along with reducing the pitch of the wiring pattern 23.
FIG. 10 shows a COF semiconductor apparatus (hereinafter, "conventional apparatus 4") in which the width of the wiring pattern 23 is smaller than that of the wiring pattern 23 employed in the conventional apparatus 2 shown in FIG. 6.
As shown in FIG. 10, with the conventional apparatus 4, the defect is prevented even if the bump electrode 25 is displaced when connected to the wiring pattern 23 in the case in which the wiring pitch is reduced. Specifically, the wiring pattern 23 is prevented from coming into contact with an adjacent bump electrode 25 to the bump electrode 25.
However, narrowing the width of the wiring pattern 23 as shown in FIG. 10 results in degrading mechanical strength of the wiring pattern 23 and bond strength between the wiring pattern 23 and the insulating tape 21. This causes a problem that the wiring pattern 23 is disconnected or peels off.
FIG. 7 shows the invention disclosed in Patent Document 1 (conventional apparatus 3). According to Patent Document 1, in order to prevent disconnection of the wiring pattern 23 in the vicinity of the opening section 22a of the solder resist 22, which disconnection is likely to occur when different temperatures are applied repeatedly, the width (wiring width) of the wiring pattern 23 is greater in the vicinity of an edge of the opening section 22a of the solder resist 22 than in the connecting section (inner lead section) that electrically connects the wiring pattern 23 and the semiconductor device 24. Patent Document 1 makes, however, no particular mention of the width of the wiring pattern 23 in the inner lead section.

Tape carrier, semiconductor apparatus, and semiconductor module apparatus


A dyestuff for heat-sensitive transfer record is here disclosed which can be represented by the formula (1) ##STR1## wherein R.sub.1 is a hydrogen atom, alkyl group having 1 to 8 carbon atoms or cycloalkyl group; R.sub.2 is a hydrogen atom, halogen atom, alkoxy group which may be substituted, alkylthio group which may be substituted or arylthio group which may be substituted; R.sub.3 is a branched alkyl group having 3 to 5 carbon atoms, O-substituted oxycarbonyl group, N-substituted aminocarbonyl group in which an N-substituted group may form a ring, or a substituted or unsubstituted heterocyclic ring having two or more atoms of one or more kinds selected from the group consisting of a nitrogen atom, oxygen atom and sulfur atom; and when R.sub.1 is a hydrogen atom, R.sub.3 is a branched alkyl group having 3 to 5 carbon atoms, or a substituted or unsubstituted heterocyclic ring having two or more atoms of one or more kinds selected from the group consisting of a nitrogen atom, oxygen atom and sulfur atom;. and there are also disclosed an ink for heat-sensitive transfer record and a transfer sheet in which the above-mentioned dyestuff is used.

(i) Field of the invention
The present invention relates to a dyestuff for heat-sensitive transfer record (hereinafter abbreviated to "sublimable dyestuff"), an ink composition for heat-sensitive transfer record and a transfer sheet which can be used in color hard copies and the like utilizing a sublimation heat transfer record system.
(ii) Description Prior Art
A heat transfer record system using a sublimable dyestuff is one of the heat transfer print systems which comprise forming a transfer sheet by coating a thin condenser paper or PET film having a thickness of several microns with an ink of a sublimable dyestuff, and then selectively heating the transfer sheet by means of a heat-sensitive head to transfer the dyestuff to a record paper which is a material to be recorded. Nowadays, the heat transfer record system has been used as a means for the image record (hard copy) of much image information.
The sublimable dyestuffs which are used in the present invention are required to have abundant colors and strong adhesive force, and to be excellent in color mixing properties and stability. In the above-mentioned record system, the amount of the dyestuff to be sublimated depends upon heat energy, and so the density of the transferred dyestuff can be analogically controlled. This is a major feature which other printing systems cannot possess.
As yellow sublimable dyestuffs, there are quinophthalone compounds having excellent light resistance and fastness (Japanese Patent Laid-open Nos. 53565/1985, 18928-9/1988 and 182192/1988), but most of these dyestuffs lack both of a high sublimation speed and the stability of a transferred image. The development of dyestuffs which can meet the optimum requirements of sublimable dyestuffs has been sought.

Dye for heat-sensitive transfer record, ink composition for heat-sensitive transfer record, and transfer sheet


An object of the present invention is to provide a battery monitoring device in which communication quality is stabilized and improved. Detection boards are mounted respectively on a plurality of cells arranged in a line, and respectively have a first antenna for wirelessly communicating status information of the mounted cells. A second antenna for receiving the status information transmitted from the first antenna is mounted on an ECU board. The plurality of detection boards and the ECU board are disposed on upper surfaces of the plurality of cells as the same plane. The plurality of detection boards are arranged in a line along an arrangement direction. The ECU board is disposed at the center in the arrangement direction of the cells.

As a battery monitoring device for monitoring the state of a battery having a plurality of cells or a single cell, for example, those shown in Patent Literatures 1 and 2 have been proposed. The battery monitoring device shown in Patent Literatures 1 and 2 includes: a plurality of detection units that detect status information of each cell; and an ECU to which the status information from the plurality of detection units is transferred.
In Patent Literatures 1 and 2, a first antenna is mounted on a detection unit of each cell, and a plurality of second antennas disposed opposite to the first antenna of the detection unit are provided on a mounting member of a battery. By connecting the second antennas to the ECU, the status information is transferred wirelessly. However, it is necessary to provide the second antennas as many as the number of cells, and to connect the plurality of second antennas to the ECU, which causes a cost problem.
Therefore, it is desirable that only one second antenna can be mounted on the ECU to receive information from a plurality of detection units. However, depending on the arrangement of the detection unit and the ECU, another detection unit may be arranged on the communication path between the ECU and the detection unit, which may hinder the communication. Also, when communication cannot be made directly from the detection unit to the ECU, communication with the ECU via another detection unit (relay unit) is also conceivable. However, even in such a case, another detection unit may be disposed between the detection unit and the relay unit, which may hinder communication.


Disclosed is a liquid crystal display device comprising gate line; a data line intersecting with the gate line over the gate line; a first electrode of transparent metal material comprising: a first portion elongated over the data line along the first direction and perpendicularly intersecting with the data line; a second portion comprising a plurality of branches each elongated along the second direction starting from the first portion of the first electrode toward the gate line; and a third portion separated by a predetermined distance along the second direction with the gate line, and elongated along the first direction starting from the longest branch to a space formed between the shortest branch and its closest branch; a second electrode of transparent metal material, formed on the same plane as the first electrode, the second electrode having a first portion corresponding to the second portion of the first electrode and a second portion corresponding to the third or first portion of the first electrode.

1. Field of the Invention
The present invention relates to a liquid crystal display with enhanced response speed, transmittance, and aperture ratio and a method for manufacturing the same.
2. Description of the Related Art
Liquid crystal displays are widely used in television and graphic displays. Especially, since active matrix liquid crystal displays has high response speed and are compatible in display devices with many pixels, they greatly contribute to realizing high definition and larger sized displays.
These liquid crystal display devices comprise a pair of transparent glass substrates, thin film transistors and pixel electrodes formed on one of the glass substrates, and color filters, and counter electrodes formed on the other glass substrate. Liquid crystal material is injected and sealed inside the space between two glass substrates.
Twisted nematic mode liquid crystals are widely in use recently because of their superior optical characteristics. The liquid crystal molecules in the twisted nematic mode are parallel to the upper and lower glass substrates when no voltage is introduced to the same. Also, the molecules are continuously arranged so that a twisted angle between the upper most molecules and lower most molecules has 90.degree.. When voltage is introduced to the glass substrates facing each other, an electric field perpendicular to the glass substrates is formed and the liquid crystal molecules are arranged along the electric field. However, since the liquid crystal molecules of the twisted nematic(hereinafter abbreviated as TN) liquid crystal displays can be arranged only in one direction, a viewing angle is narrow.
Various technologies to enhance the viewing angle have been suggested. One of them is an IPS(In-Plane Switching) mode liquid crystal display. In the IPS mode liquid crystal display, counter electrodes usually formed on the upper substrate are formed on the lower glass substrate where pixel electrodes are formed. Hence, an electric field parallel to the substrates is formed between the pixel electrode and the counter electrode.
Referring to FIG. 1 and FIG. 2, the IPS mode liquid crystal display device comprises a gate line 2A in a column direction formed on a surface of a lower substrate 1 for scan image information to the upper part of the lower substrate; a counter electrode 2B on the same plane where the gate line 2A is, separated from the gate Line 2A by a predetermined distance; a gate insulation film 3 formed on a surface of the resultant structure where the gate line 2A and the counter electrode 2B are formed; a data line 5A which defines a pixel domain together with the gate line 2A, formed in the column direction and perpendicular to the gate line 2A that is separated by the gate insulation film 3; and a pixel electrode 5B lying on the same plane as the data line 5A over the counter electrode 2B, overlapping with some parts of the counter electrode 2B. The counter electrode 2B comprises a first portion 2BA and a second portion 2BC which are parallel to the gate line 2A; a third portion 2BB arranged perpendicularly to the first and second portion 2BA, 2BC, formed between a middle part of the first portion 2BA and a middle part of the second portion 2BC. The pixel electrode 5B has a first portion 5BA and a second portion 5BB which both have identical length and parallel to the gate line 2A; third and fourth portions 5BC, 5BD, both parallel to the data line 5A, respectively connected to the end parts of the first portion 5BA and the second portion 5BB; and a fifth portion 5BE which is protruded from the third portion 5BC, parallel to the data line 2A.
The first and second portions 2BA, 2BC of the counter electrode 2A, which overlaps with the pixel electrode 5B, are employed as an electrode of a capacitor for maintaining the liquid crystal molecules in a certain form for a predetermined period. One end of the fifth portion 5BE of the pixel electrode 5A where the pixel electrode 5B and the gate line 2A intersect, is employed as a drain for a thin film transistor. Furthermore, the semiconductor layer 4 formed at a predetermined part of the top surface of the gate insulation film 3 serves as a channel for a thin film transistor. One end of the data line 5A intersecting with the semiconductor layer 4 formed on the gate line 2A is employed as a source for a thin film transistor.
The above described gate line 2A and the counter electrode 2B is made of one selected from a group consisting of aluminum, titanium, tantalum, and chrome and combination thereof. The gate insulation film 3 is made by oxidizing one of the above metals or forming double insulation layer. The data line and the pixel electrode are formed by depositing one of the above mentioned metals and patterning the same.
As it is shown in the sectional view of FIG. 2, an electric field F1 parallel to the glass substrate is formed between the pixel electrode 5B and the counter electrode 2B. However, since the pixel electrode and the counter electrode are rectangular form, the edge effect causes a parabolic electric field F2 at the edges of these electrodes. The liquid crystal molecules are arranged along the electric field. Hence the longer axis of the molecules along the electric field F1 is parallel to the glass substrates. However, since the longer axis of the liquid crystal molecules has a slanting angle to the glass substrates due to the electric field F2, the liquid crystal molecules situated at the top surface of the electrodes 5BC, 2BC, 5BB which have longer axis perpendicular to the glass substrates, do not react to the introduced voltage. Thus, the response speed and the transmittance are inherently low.
The transmittance of a conventional liquid crystal display where the distance between the pixel electrode and the counter electrode is 210 .mu.m, the width of the pixel electrode or the counter electrode is 20 .mu.m, the liquid crystal molecules have a slanting angle of 22.degree. to the horizontal axis, and the introduced voltage to the pixel electrode is 8 V, is shown in FIG. 3, for example of the above description. In FIG. 3, the X stands for transmittance to the voltage introduced to the lower substrate, and the Y stands for a height of the liquid crystal layer from the lower substrate with the pixel electrode and the counter electrode. The transmittance after 100 ms from introducing voltage is about 38% and that before 100 ms is 30% or less.
Also, as the pixel electrode and the counter electrode are made of non-transparent metal, the transmittance is close to 0% in these areas. Hence, the aperture ratio of the liquid crystal display is reduced.

Liquid crystal display device with enhanced response speed, transmittance, and aperture ratio and method for manufacturing the same

Hyundai Electronics Industries Co., Ltd.


An example method is provided and includes maintaining at a network element a flow table, in which the flow table comprises a plurality of flow table entries and in which each of the flow table entries corresponds to one of a plurality of active data flows in a network, and, subsequent to receipt at the network element of a data packet of one of the active flows, characterizing the one of the active flows as a large flow or a short flow using values contained in the flow table entry corresponding to the one of the active flows. The method further includes processing the received packet in accordance with the characterization.

A variety of applications and platforms have recently arisen that require very low latency in the data centers in which they are implemented. One such application is "MapReduce," which follows the request-response (or request-reply) model. Request-response is one of the basic techniques used by computing devices to communicate with one another and involves a first computing device sending a request for data to a second computing device and the second device responding to the request. Typically, there will be a series of interchanges until the complete message is sent from the second computing device to the first computing device. In MapReduce applications, the request is split into multiple smaller sub-requests, each of which may be sent to one of multiple different servers in a data center. The transaction is deemed complete once responses to all of the sub-requests have been received from the servers. Because the last response received determines completion of the transaction, the Once the response to each of the sub-requests is received from all of the servers, the transaction is complete. Since the last response received determines completions of the transaction, the tail latency of the individual sub-requests are important and required to be as small as possible.

Technique for achieving low latency in data center network environments


In the BGA package and its manufacturing method, a bonding pad is etched from the exposed surface to a part of the insulation layer-coated region so as to form a solder contact side having a dish configuration, which is planar at a bottom center and slanted at a periphery. With this bent structure of the dish configuration, the bonding pad provides an increased bonding area for the solder, so that the BGA package substrate is enhanced in reliability.

1. Field of the Invention
The present invention relates to a BGA package and a method of manufacturing the same. Particularly, the present invention relates to a BGA package which has superior reliability, showing excellent interfacial properties and resistance to external impact. Also, the present invention is concerned with a method of manufacturing the BGA package, in which a bend having a planar upper surface and a slanted periphery is formed between a solder contact side of a bonding pad and an insulation layer, thereby providing an increased bonding area for a solder ball.
2. Description of the Related Art
Although integrated circuits have been developed for slimness and lightness, the number of leads extending from integrated circuit packages is increasing rather than decreasing. As a solution to the problem resulting from a small package carrier requiring a large number of leads, a PGA (pin grid array) carrier has been developed. Able as it is to be provided with many leads to its small area, the PGA carrier suffers from disadvantages that pins or leads are so weak that they break readily and that there are limits to high density integration.
An approach to overcoming the disadvantages of PGA is to use recently popularized BGA package substrates. BGA package substrates employ solder balls, which are finer than pins, thereby allowing high density integration thereon. Mostly, BGA package substrates are used for mounting semiconductor chips.
In order to better understand the background of the present invention, a description is given of a conventional BGA package substrate, below.
With reference to FIG. 1, a conventional semiconductor chip-mounted BGA package provided with solder balls 60 instead of pins is depicted in a cross sectional view.
First, a plurality of CCLs (copper clad laminates) 10 is prepared, each CCL 10 undergoing a typical photolithographic process to form a predetermined circuit pattern thereon.
Next, the CCLs 10, each having a predetermined circuit pattern thereon, are pressed against each other to provide a laminate structure which is then processed to form a via hole 20, followed by plating the via hole 20 with a copper foil 30 to electrically interconnect the circuit patterns formed on each CCL 10.
On the copper foil 30 formed on a side of the laminated CCL structure, a circuit pattern for a semiconductor chip 40-mounting bonding pad, e.g. a bond finger 50, is constructed by a photolithographic process. Likewise, a circuit pattern for bonding pads to which solder balls 60 are attached, that is, a circuit pattern for solder pads 70, is also constructed on a copper foil 30 formed on another side of the CCL structure.
Following the formation of the circuit patterns for the bonding pads 50 and 70 on the copper foils 30 of the CCL 10, PSR (photo imageable solder resist mask) ink is applied to form an insulation layer 80 with the aim of protecting the circuit patterns on the copper foils 30 as well as preventing the formation of a solder bridge between the circuit patterns during a soldering process.
Subsequently, with the aid of a diazo film having thereon a circuit pattern for exposing the bonding pad, a circuit process is conducted to remove the insulation layer 80 coated on the area where the bond finger 50 or the solder pad 70 will be formed.
After the formation of the bonding pad, such as the bond finger 50 or the solder pad 70, a finishing process for preventing the oxidation of the bonding pad is conducted to form a Ni/Au-plated layer on the bonding pad by electroless gold plating.
In more detail, the bonding pad, e.g., the bonding finger 50 or the solder pad 70, is plated with nickel to form a nickel-plated layer 91 to a predetermined height, e.g., 3-5 μm.
Gold, when applied to a bare bonding pad 50 or 70, diffuses into the copper texture of the bonding pad, so that the gold-plated layer cannot be subjected to the finishing process. Accordingly, nickel plating precedes gold plating in order to prevent gold, when plated, from diffusing into the copper texture.
Next, a gold-plated layer 92 is formed to a predetermined height, for example, 0.03-0.07 μm on the nickel-plated layer 91 so as to impart affinity for the solder balls 60. Therefore, a BGA package is obtained, with the bond finger for mounting a semiconductor device and the solder pad for attaching solder being finished.
In this conventional BGA package, the formation of the Ni/Au-plated layer 90 not only prevents the bonding pad, made from electrically conducting metal such as copper (Cu), that is, the solder pad 70, from being oxidized, but also provides the bonding pad with greater affinity for the solder balls 60; however, intermetallic compounds are produced due to the reaction between the nickel of the plated layer 90 and the tin of the solder balls 60.
A high-speed impact test such as a drop test revealed that cracking readily occurs at the interface between the Ni/Au-plated layer 90 and the solder balls due to the brittleness of Au in the presence of the intermetallic compounds including Au formed by the reaction of the Ni/Au layer with the solder, and thus that the solder balls 60 are readily detected from the solder pads.
As a solution to the problem, a BGA packaging process is suggested which employs an OSP (organic solderability preservative), instead of the Ni/Au-plated layer 90, in finishing the semiconductor chip-mounting bonding pad or the solder-bonding solder pad.
In lieu of the formation of the Ni/Au-plated layer 90 on the solder pad to which solder is attached, an OSP is layered on the solder pad to conduct the finishing process for the open solder pad.
Thereafter, the OSP-coated BGA package substrate is subjected to an in-line process consisting of prebake, die attach, die attach curing, plasma and wire bonding, through which a semiconductor device is connected onto the bonding pad formed on a side of the BGA package substrate.
The in-line process through which a semiconductor device is attached onto the bonding pad is followed by a back-end process consisting of prebake, plasma, pre-mold curing, post-mold curing, solder attach and IR reflower, through which a solder is attached to the solder pad formed on another side of the BGA package substrate.
However, the BGA package process using an OSP is disadvantageous in that the OSP applied to the plated layer where the solder pad is formed is damaged by heat during the in-line process or the back-end process as shown in FIG. 3. Especially, the PMC step of the back-end process, which is conducted at 175° C. or higher, causes fetal damage to the OSP.
With reference to FIG. 4, a ball shear test shows that the OSP thermally damaged during the in-line process or the back-end process remains in the plated layer at which the bonding finger or solder pad of the BGA package substrate is formed.
As shown in FIG. 5, when a solder is jointed to a planar, plated layer 170 which is not etched in a direction to a predetermined depth and in which a thermally damaged OSP 200 remains, the remaining OSP 200 decreases the bonding area between the plated layer 170 and the solder balls 60 and prevents the reaction between the copper of the plated layer 170 and the tin of the solder balls 60 to inhibit the formation of intermetallic compounds 700.
As a result, the BGA package becomes unreliable, showing the formation of a non-wetting zone on a solder side and poor interfacial properties. For example, as shown in FIG. 6, the solder balls 60 are not bonded to the plated layer 170 or readily detaches upon external impact.

BGA package with concave shaped bonding pads


A strained silicon layer fabrication employs a substrate having successively formed thereover: (1) a first silicon-germanium alloy material layer; (2) a first silicon layer; (3) a second silicon-germanium alloy material layer; and (4) a second silicon layer. Within the fabrication each of the first silicon-germanium alloy layer and the second silicon-germanium alloy layer is formed of a thickness less than a threshold thickness for dislocation defect formation, such as to provide attenuated dislocation defect formation within the strained silicon layer fabrication.

1. Field of the Invention
The present invention relates generally to strained silicon layer structures employed within semiconductor products. More particularly, the present invention relates to reduced dislocation defect density strained silicon layer structures employed within semiconductor products.
2. Description of the Related Art
As semiconductor product performance requirements have increased, so also have evolved novel semiconductor materials and structures which provide enhanced semiconductor product performance. Included among such novel materials and structures are strained silicon materials and structures which may be employed as substrates when forming semiconductor devices. Strained silicon materials and structures are desirable as semiconductor substrates insofar as strained silicon materials provide for enhanced carrier mobility and thus enhanced performance of semiconductor devices.
While strained silicon materials and structures are thus desirable in the art of semiconductor fabrication, they are nonetheless not entirely without problems. In that regard, it is often difficult in the art of semiconductor fabrication to provide strained silicon layer structures with attenuated strain induced defects, such as strain induced dislocation defects.
It is thus desirable in the semiconductor fabrication art to provide strained silicon layer structures with attenuated strain induced defects.
It is towards the foregoing object that the present invention is directed.
Various strained silicon layer structures having desirable properties, and methods for fabrication thereof, have been disclosed in the semiconductor fabrication art.
Included among the strained silicon layer structures and methods, but not limiting among the strained silicon layer structures and methods, are strained silicon layer structures and methods disclosed within: (1) Ismail et al., in U.S. Pat. No. 5,534,713 (a strained silicon layer structure suitable for fabrication of complementary metal oxide semiconductor (CMOS) field effect transistor (FET) devices); (2) Ek et al., in U.S. Pat. No. 5,759,898 (a strained silicon layer structure with attenuated dislocation defects); (3) Liaw et al., in U.S. Pat. No. 5,891,769 (a thermal annealing method for forming a strained silicon layer structure); and (4) Sugiyama et al., in U.S. Pat. No. 6,326,667 (an oxygen implant method for forming a strained silicon layer structure).
The teachings of each of the foregoing references are incorporated herein fully by reference.
Desirable in the semiconductor fabrication art are additional strained silicon layer structures with attenuated strain induced defects.
It is towards the foregoing object that the present invention is directed.

Strained silicon layer fabrication with reduced dislocation defect density

Taiwan Semiconductor Manufacturing Co., Ltd.


Methods of and devices for automatically reducing and/or eliminating false alarms to the call centers are disclosed. The method of reducing a false alarm notification to a call center can comprise receiving a triggered event notification on a mobile device, requesting a user to unlock the mobile device, and requesting the user to confirm a triggered alarm or dismiss the trigger notification using the mobile device using a non-GUI based user interface.

Typically, triggered warning signals of a security system (e.g., a home security system) are directly sent to a service providing unit (e.g., a call center, a home security monitoring and response center, or Tele-Medical Call Center). Such warning signals generally require the service providing unit to maintain a service person that calls a designated person of the service subscriber to confirm a dispatch of an emergency assistant (e.g., police, fire, or ambulance) or to dismiss the warning signal, which takes substantial resources including numbers of service people and engaged service time. Nonetheless, a large ratio/number of all the warning signals are false alarms or situations that do not require the emergency assistant, which results in inefficiency in terms of wasted man hours for all service providers.
In the U.S., there are at least 400 k self-triggered false alarms that occur every year. The average costs for a call is at least $20. Thus, the estimated costs for the false alarms are at least 8 million dollars a year, which results in great wastes in resources.

AI-based monitoring system for reducing a false alarm notification to a call center


Embodiments of a device to move waste toner within an image forming device. In one embodiment, waste toner is formed during the image formation process. The waste toner is captured and moved through a first conduit. The conduit includes an outlet for passing the waste toner to a second conduit. The door is positionable between an open orientation to allow the waste toner to discharge into the second conduit, and a closed orientation. The second conduit includes an inlet for receiving the waste toner. The interface between the first and second conduits allows for the door to move between the open and closed orientations. The interface also greatly reduces or prevents the waste toner from leaking as it passes from the first conduit into the second conduit.

Image forming devices form images through a toner transfer process that transfers toner particles to a media sheet. The process includes forming a latent image on a photoconductive member with a laser device. The toner particles originally stored in a reservoir are attracted to the latent image and transferred from the reservoir to the photoconductive member. The toner particles on the photoconductive member are than passed either directly to the media sheet, or transferred to an intermediate member and then transferred to the media sheet. During the toner transfer process, some toner particles are not transferred and remain on the photoconductive member or intermediate member. These particles should be removed prior to forming the next toner image.
The removed toner particles, also referred to as waste toner, may be transported within the image forming device and stored for disposal. Alternatively, the waste toner may be recycled and re-introduced back into the reservoir for forming a subsequent toner image. In either event, the waste toner should be transported in a leak-free system. The transport system may include conduits that lead from one section of the image forming device to a second section of the device. Further, the transport system may pass or hand-off the waste toner from a first conduit to a second conduit.
The waste toner has the consistency of a fine powder that is prone to leak from the transport system. Small cracks or openings in the transport system, such as at the hand-off areas of one conduit to a second conduit, may result in toner leakage. Waste toner that leaks from the transport system gathers within the interior of the image forming device. The leaked toner may attach to a media sheet moving through the device resulting in a print defect. Alternatively, the leaked toner may attach to a user, such as when the user is replacing a cartridge or other internal component. Either leakage situation is problematic and should be kept to a rare occasion, or completely eliminated.

Device for moving toner within an image forming device


A NOR flash nonvolatile memory device provides the memory cell size and a low current program process of a NAND flash nonvolatile memory device and the fast, asynchronous random access of a NOR flash nonvolatile memory device. The NOR flash nonvolatile memory device has an array of NOR flash nonvolatile memory circuits that includes charge retaining transistors serially connected in a NAND string such that at least one of the charge retaining transistors functions as a select gate transistor to prevent leakage current through the charge retaining transistors when the charge retaining transistors is not selected for reading. The topmost charge retaining transistor's drain is connected to a bit line parallel to the charge retaining transistors and the bottommost charge retaining transistor's source is connected to a source line and is parallel to the bit line. The charge retaining transistors are programmed and erased with a Fowler-Nordheim tunneling process.

1. Field of the Invention
This invention relates generally to nonvolatile memory array structure and operation. More particularly, this invention relates to a NAND based NOR flash nonvolatile memory device structure and operation.
2. Description of Related Art
Nonvolatile memory is well known in the art. The different types of nonvolatile memory include Read-Only-Memory (ROM), Electrically Programmable Read Only Memory (EPROM), Electrically Erasable Programmable Read Only Memory (EEPROM), NOR Flash Memory, and NAND Flash Memory. In current applications such as personal digital assistants, cellular telephones, notebook and laptop computers, voice recorders, global positioning systems, etc., the Flash Memory has become one of the more popular types of Nonvolatile Memory. Flash Memory has the combined advantages of the high density, small silicon area, low cost and can be repeatedly programmed and erased with a single low-voltage power supply voltage source.
The Flash Memory structures known in the art employ a charge retaining mechanism such as a charge storage and a charge trapping. The charge storage mechanism, as with a floating gate nonvolatile memory, the charge representing digital data is stored on a floating gate of the device. The stored charge modifies the threshold voltage of the floating gate memory cell determine that digital data stored. In a charge trapping mechanism, as in a Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) or Metal-Oxide-Nitride-Oxide-Silicon (MONOS) type cell, the charge is trapped in a charge trapping layer between two insulating layers. The charge trapping layer in the SONOS/MONOS devices has a relatively high dielectric constant (k) such Silicon Nitride (SiNx).
A present day flash nonvolatile memory is divided into two major product categories such as the fast random-access, asynchronous NOR flash nonvolatile memory and the slower serial-access, synchronous NAND flash nonvolatile memory. NOR flash nonvolatile memory as presently designed is the high pin-count memory with multiple external address and data pins along with appropriate control signal pins. One disadvantage of NOR flash nonvolatile memory is as the density is doubled, the number of its required external pin count increases by one due to the adding of one more external address pin. In contrast, NAND flash nonvolatile memory has an advantage of having a smaller pin-count than NOR with no address input pins. As density increases, the NAND flash nonvolatile memory pin count is always kept constant. Both main-streamed NAND and NOR flash nonvolatile memory cell structures in production today use a one charge retaining (charge storage or charge trapping) transistor memory cell that stores one bit of data as charge or as it commonly referred to as a single-level program cell (SLC). They are respectively referred as one-bit/one transistor NAND cell or NOR cell, storing a single-level programmed data in the cell.
The NAND and NOR flash nonvolatile memory provide the advantage of in-system program and erase capabilities and have a specification for providing at least 100K endurance cycles. In addition, both single-chip NAND and NOR flash nonvolatile memory product can provide giga-byte density because their highly-scalable cell sizes. For instance, presently a one-bit/one transistor NAND cell size is kept at ˜4λ2 (λ being a minimum feature size in a semiconductor process), while NOR cell size is ˜10λ2. Furthermore, in addition to storing data as a single-level program cell having two voltage thresholds (Vt0 and Vt1), both one transistor NAND and NOR flash nonvolatile memory cells are able to store at least two bits per cell or two bits/one transistor with four multi-level threshold voltages (Vt0, Vt1, Vt2 and Vt03) in one physical cell.
Currently, the highest-density of a single-chip double polycrystalline silicon gate NAND flash nonvolatile memory chip is 63 Gb. In contrast, a double polycrystalline silicon gate NOR flash nonvolatile memory chip has a density of 2 Gb. The big gap between NAND and NOR flash nonvolatile memory density is a result of the superior scalability of NAND flash nonvolatile memory cell over a NOR flash nonvolatile memory. A NOR flash nonvolatile memory cell requires 5.0V drain-to-source (Vds) to maintain a high-current Channel-Hot-Electron (CHE) programming process. Alternately, a NAND flash nonvolatile memory cell requires 0.0V between the drain to source for a low-current Fowler-Nordheim channel tunneling program process. The above results in the one-bit/one transistor NAND flash nonvolatile memory cell size being only one half that of a one-bit/one transistor NOR flash nonvolatile memory cell. This permits a NAND flash nonvolatile memory device to be used in applications that require huge data storage. A NOR flash nonvolatile memory device is extensively used as a program-code storage memory which requires less data storage and requires fast and asynchronous random access.
A two-transistor NOR flash nonvolatile memory cell is formed of two NMOS transistors that is structured as a single-level program cell. The top transistor of the two-transistor NOR cell is a floating-gate transistor and the bottom transistor is a regular NMOS select transistor. Only the top 1T NAND cell has the capability to store data. With only one transistor of the two-transistor NOR flash nonvolatile memory cell retaining data, the overhead of this NOR flash nonvolatile memory cell is one select is transistor per NAND cell.
U.S. Pat. No. 7,263,003 (Edahiro, et al.) describes a two-transistor flash memory device using a replica cell array to control the precharge/discharge and sense amplifier circuits of the primary cell array.
U.S. Pat. No. 5,596,523 (Endoh, et al.) provides a NOR cell type EEPROM memory cell array section. Every two neighboring NOR cells are connected to a corresponding bit line at which the drain of one memory cell transistor and the source of the other cell transistor are connected together. The other source and drain of those cell transistors are coupled together to a source line. The Source line is provided with a select transistor.
U.S. Pat. No. 6,765,825 (Scott) describes a differential NOR memory cell having two floating gate transistors. Each of the drain terminals of the transistors is coupled to a corresponding differential bit line. The source terminal of both transistors are coupled to a common current source or sink. Each of the control gate terminals are coupled to a corresponding word line, which may be the same as or different than the corresponding word line that the other control terminal is connected to. The floating gate transistor may be five-terminal devices that include an additional well terminal. In that case, a different set of bit lines is used to program the EEPROM memory cell as are used to read the EEPROM memory cell. While the drain terminals are coupled to the differential read bit lines, each of the well terminals is coupled to a corresponding differential program bit line.
U.S. Patent Application 2006/0181925 (Specht, et al.) a nonvolatile memory cell arrangement where memory transistors are arranged in rows and columns. The source/drain terminals of the memory transistors of the first column are coupled to to conductor tracks of a different metallization plane than the first source/drain terminals of the memory transistors of the second column. In this way, it is now possible to arrange the memory transistors of adjacent columns in a memory arrangement closer to one another.

NAND based NMOS NOR flash memory cell, a NAND based NMOS NOR flash memory array, and a method of forming a NAND based NMOS NOR flash memory array


According to one embodiment, a semiconductor memory device includes a memory cell array, a first circuit, and a second circuit. The first circuit executes program and read. The program is processing for changing a threshold voltage of a memory cell to a voltage according to data. The data includes first data of a bit and second data of a bit. The program of the second data is executed after the program of the first data. The read includes measuring the threshold voltage. The second circuit manipulates a flag in accordance with execution of the program of the second data. In a case where the second data is a target of the read, the second circuit refers to the flag. In a case where the flag indicates non-execution of the program of the second data, the second circuit aborts the measuring before the measuring of the threshold voltage is completed.

A semiconductor memory device having a memory cell and capable of storing data to the memory cell is widely known. The semiconductor memory device injects as much as electrical charge as an amount corresponding to the data into the memory cell. The threshold voltage of the memory cell changes in accordance with the amount of the electrical charge held in the memory cell. The semiconductor memory device determines the data stored in the memory cell by identifying, from among a plurality of ranges of voltages, a range including the threshold voltage of the memory cell.
In recent years, the number of bits of data stored in a single memory cell tends to be increased. In accordance with the increase in the number of bits of data stored in a single memory cell, the algorithm for determining the data becomes complicated, and this worsens the performance of reading.

Semiconductor memory device, control method, and memory system


Methods and compositions are provided for modified cells, where a chimeric protein consisting of a ligand binding domain fused to an action domain is employed which initiates a signal which activates a biological process: transcription of at least one gene, usually a second construct introduced into the host cells; exocytosis; or an extracellular process. The second construct optimally present provides for a promoter which responds to a transcriptional activation action domain to provide for transcription, when an appropriate ligand binds to the ligand binding domain. Exemplary of the system is the use of an FKBP/CD3.zeta. or transcription factor fusion protein, using dimeric FK506 or FK520 as the ligand and a promoter responsive to NF-AT or other transcription factor requiring two molecules for transcriptional activation.

The genomic complexity of mammals, particularly humans, allows for numerous genetic and physiological changes during conception, development of the fetus, and during adult life. Subsequently, pathologic changes may occur, due to autoimmune diseases, exposure to mutating agents, and the like. In addition, there are various recessive genes, which can result in diseases when the resulting progeny is homozygous for the recessive trait. For the most part, individuals having a variety of genetic diseases or pathological indications associated with autoimmune diseases, such as diabetes, have, for the most part, been dependent upon the administration of drugs. Drugs have not been entirely satisfactory for a number of different reasons. Frequently, the drugs have side effects which are detrimental to the host and result in pathological events. For some diseases, drugs are merely palliative or nay not even be available. In other situations, regular administration of drugs can be difficult to maintain, particularly with the elderly or mentally impaired, who find it difficult to perform a strict regimen.
With The advent of recombinant technology, the possibility of modifying endogenous cells or cells which can be safely administered to a host has offered new avenues of investigation for therapeutic treatments. However, there are many concerns related to the use of gene therapy. In some cases, one is solely concerned with introducing cells into the host which can function in place of defective wild-type cells. In other situations, one may wish to provide cells which can produce a secreted product which can then fulfill a desired function. However, in normal physiological operation, the secretion of product is usually controlled based on need and, frequently, may involve providing a localized concentration of the secreted product, rather than a systemic availability. It is therefore of substantial interest to be able to develop gene therapies, which can meet manifold therapeutic needs as required by the sick and impaired.
The levels of production of proteins by human cells varies by as much as 1 to 10.sup.6 fold during development and in response to physiologic and pathologic stimuli. (E. H. Davidson, Gene Activity in Development 1986, 3rd Edition, Academic Press, Orlando, Fla.) Since any protein if overexpressed nay have toxic and harmful effects, it is essential that any introduced gene be carefully regulated.
Furthermore, there is usually a minimum level of therapeutic effect. By monitoring the level of the protein product in the tissue, organ or vascular system, in a system subject to extrinsic control, one can determine the level of the protein product, and use the extrinsic control to provide the desired level.
Besides intracellular opportunities for therapy, there are also possibilities where control of extracellular events may be of interest. In a variety of situations, such as homing, blood coagulation, clot dissolution, cell activation, and the like, the ability to bring together two or more different proteins rapidly could provide for new opportunities for controlling physiology and therapies.

Regulated transcription of targeted genes and other biological events

Board of Trustees of the Leland Stanford Junior University

President and Fellows of Harvard College


Described is an approach for recovering the failure of a transaction. According to the approach, a first change and a third change is made to a first resource and a second change is made to a second resource. The second change was made after the first but before the third. However, to recover the failure of the transaction, a recovery record for the third change is applied before the recovery record for the second change. Also described is an approach involving establishing links that link together a set of undo records that contain changes made to the particular resource. Also described is an approach for applying two or more undo records in parallel.

In typical database systems, users store, update and retrieve information by submitting commands to a database application. To be correctly processed, the commands must comply with the database language that is supported by the database application. One popular database language is known as Structured Query Language (SQL).
A logical unit of work that is atomic and comprised of one or more database language statements is referred to as a transaction. In a database server, an area of system memory is allocated and one or more processes are started to execute one or more transactions. The database server communicates with connected user processes and performs tasks on behalf of the user. These tasks typically include the execution of transactions. The combination of the allocated system memory and the processes executing transactions is commonly termed a database instance.
A buffer cache resides in a portion of the system memory and holds database information. Buffers in the buffer cache hold copies of data blocks that have been read from data files. The buffers are shared by all user processes concurrently connected to the instance. When a transaction desires to make a change to a data block, a copy of the data block is loaded into a buffer and the change is made to the copy of the data block stored in the database buffer cache in dynamic memory. Afterwards, a database writer writes the modified blocks of data from the database buffer cache to the data files on disk.
The system memory also contains a redo log buffer. A redo log buffer is a buffer that holds information about update operations recently performed by transactions. This information is stored in redo entries. Redo entries contain the information necessary to reconstruct, or redo, changes made by operations such as INSERT, UPDATE, DELETE, CREATE, ALTER, or DROP, for example. Redo entries are generated for each change made to a copy of a data block stored in the database buffer cache. The redo log buffer is written to online redo log file(s) on disk. The records in the online redo log file(s) on disk are referred to as redo logs.
An instance failure can occur when a problem arises that prevents an instance from continuing work. Instance failures may result from hardware problems such as a power outage, or software problems such as an operating system or database system crash. Instance failures can also occur expectedly, for example, when a shutdown/abort statement is issued.
Due to the way in which database updates are performed to data files in some database systems, at any given point in time, a data file may contain some data blocks that (1) have been tentatively modified by uncommitted transactions and/or (2) do not yet reflect updates performed by committed transactions. Thus, an instance recovery operation must be performed after an instance failure to restore a database to the transaction consistent state it possessed just prior to the instance failure. In a transaction consistent state, a database reflects all the changes made by transactions which are committed and none of the changes made by transactions which are not committed.
A typical DBMS performs several steps during an instance recovery. First, the DBMS rolls forward, or reapplies to the data files all of the changes recorded in the redo log. Rolling forward proceeds through as many redo log files as necessary to bring the database forward in time to reflect all of the changes made prior to the time of the crash. Rolling forward usually includes applying the changes in online redo log files, and may also include applying changes recorded in archived redo log files (online redo files which are archived before being reused). After rolling forward, the data blocks contain all committed changes as well as any uncommitted changes that were recorded in the redo log prior to the crash. Rollback segments include records for undoing uncommitted changes made during the roll-forward operation. In database recovery, the information contained in the rollback segments is used to undo the changes made by transactions that were uncommitted at the time of the crash. The process of undoing changes made by the uncommitted transactions is referred to as "rolling back" the transactions.
FIG. 1 illustrates rolling forward and rolling back. Database 110 is a database requiring recovery at time t1. Database 120 represents the database after a redo log is applied at time t2. The database 120 comprises both changes made by committed transactions 121 and changes made by uncommitted transactions 122. Database 130 represents the database at time t3 after a rollback segment is applied. The database 130 comprises only changes made by committed transactions 121.
When rolling back a transaction, the DBMS releases any resources (locked resources) held by the transaction at the time of failure. Lastly, the DBMS resolves any pending distributed transactions that were undergoing a two-phase commit coordinated by the DBMS at the time of the instance failure.
One disadvantage of the prior method of recovering after a crash of an instance of a database is that undo records for all uncommitted (dead) transactions must be applied before a user is allowed to execute a new transaction to access the database system. This can take a long period of time if there are a large number of dead transactions that need to be rolled back, even if many of the undo records for dead transactions are directed to data blocks that will not be accessed by the new transaction.
One enhancement that can be used to reduce the period of time that a user must wait before executing a new transaction is by rolling back changes, on an as needed transaction-by-transaction basis, depending on the particular data blocks that are of interest to the new transaction.
However, this enhancement also suffers from inefficiencies if the rollback of a dead transaction requires undo changes to be applied to a large number of data blocks, but the new transaction only requires access to a small number of those data blocks. Thus, a user may be required to wait a large period of time for undo changes to be applied to data blocks that are not of interest to the new transaction.
Based on the foregoing, it is highly desirable to provide a method and apparatus for reducing the number of undo changes that need to be applied when a new transaction encounters a resource that is locked by a dead transaction.

This patent is subject to a terminal disclaimer.

Method and apparatus for making available data that was locked by a dead transaction before rolling back the entire dead transaction


A system and method for automatically performing start-up and overpressure relief functions in association with a primary fluid carrier such as, for example, a liquid handling pipeline or tank. The system includes a main valve for primarily exhausting air from the system as it fills with a liquid. A start-up pilot device is also provided for exhausting air from the system upon start-up, but prior to the main valve opening. Finally, an overpressure pilot device is provided to relieve overpressure situations during normal operation.

Liquid delivery and handling systems such as, for example, industrial fire sprinkler systems are adapted to accommodate a liquid such as water under pressure. As such, when the system is activated the pressurized water is exhausted through any number of nozzles or sprinklers for extinguishing the fire. Upon initial installation, for example, the various pipelines, valves, nozzles, and sprinklers art not filled with water, but rather, contain air at generally atmospheric pressure. When the system is filled with water, a process that can be referred to as "start-up," the air in the system must be exhausted through some sort of exhaust valving arrangement. This exhausting of the air can be referred to as "start-up relief." Many conventional exhaust valving arrangements include manually operable valves, which are opened upon "start-up" and manually closed when all the air is exhausted. Once all the air is exhausted, the system is completely filled with water and pressurized to a target pressure. Increases in pressure above the target pressure, which can result from environmental changes or changes in the source of water supply, for example, and can detrimentally affect the operation and useful life of the system. Therefore, some conventional systems also include an overpressure relief valving arrangement that is configured to relieve the pressure in the system back down to the target pressure, a process which can be referred to as "overpressure relief." Some conventional overpressure relief valving arrangements are either manually operated in response to an alarm, for example, or operate based on the sensing of pressure in the system. Regardless of the specific exhaust and relief valving arrangements conventionally used, the two arrangements operate independently of each other and require at least some amount of user input or attention to ensure proper "start-up relief" and/or "overpressure relief" functionality.

Backpressure regulator with easy pump start-up

EMERSON PROCESS MANAGEMENT REGULATOR TECHNOLOGIES, INC.


An input stage of a police radar detector is configured so that a near end of a mixer is coupled to an antenna for receiving high frequency signals and a far end of the mixer is coupled to the antenna for receiving low frequency signals. A local oscillator and an intermediate frequency amplifier are also coupled to the far end of the mixer. The low frequency signals, X band police radar signals, are coupled to the far end of the mixer through a band rejection filter, which serves as a diplexer, a preamplifier and a first bandpass filter. The local oscillator is coupled to the far end of the mixer through a second bandpass filter and the far end of the mixer is coupled to the intermediate frequency amplifier through a low pass filter. The high frequency signals, K band and K.sub.a band signals, are coupled to the near end of the mixer from the antenna through a high pass filter. The diplexer in combination with the first and second bandpass filters, the low pass filter and the high pass filter passively multiplex the related signals within the input stage of the police radar detector.

The present invention relates in general to police radar detectors and, more particularly, to a novel input stage for a police radar detector which input stage efficiently interconnects an antenna, a local oscillator, a mixer and an intermediate frequency amplifier within the input stage.
Police have used radar waves to monitor the speed of motor vehicles for many years. The frequencies currently licensed in the United States for police radar waves include: the X band--10.50 gigahertz (Ghz) to 10.55 Ghz; the K band--24.05 Ghz to 24.25 Ghz; and, the K.sub.a band--33.40 Ghz to 36.00 Ghz. To alert motorists of the presence of police radar, electromagnetic signals within these police radar bands are monitored using a police radar detector which issues an audible and/or visual alert upon detection of a radar signal within one of bands.
Police radar detectors are basically superheterodyne radio receivers in which the tuning of the receivers is repeatedly swept through the frequencies which are to be received or detected, i.e., the frequencies of the licensed police radar bands. A typical superheterodyne radio receiver includes a mixer for receiving electromagnetic signals and a local oscillator (LO) signal to convert the frequency of the received signals to the frequency of an intermediate (IF) amplifier with the LO being swept in frequency to tune the required frequencies. Incoming electromagnetic signals can then be received at the LO frequency plus or minus the IF frequency.
It is important to process received electromagnetic energy as efficiently as possible within a police radar detector so that weak radar signals can be effectively detected. An operator of the detector can then be alerted of the presence of police radar signals at the earliest possible time giving the operator sufficient advance notice that the operator can verify that he or she is operating their vehicle at an appropriate speed. To this end, input stages for police radar detectors must efficiently interconnect an antenna, the LO, the mixer and the IF amplifier so that there is minimal loss of each signal from the signal's source to its destination.
In the interest of advancing the art and to provide improved performance for police radar detectors, there is an ongoing need for novel and improved arrangements for input stages for police radar detectors.


A coupling for pressure lines, having a housing (10) which has a continuous conveying duct (12) for a pressurised medium and can be connected by one end to a pressure source and attached by the opposite end to a connection nipple (30), and having retaining jaws (136) which are arranged around the mouth of the conveying duct opening into the connection nipple (30) and which can be fixed by a locking mechanism in a position in which they engage around the connection nipple (30), in which the retaining jaws (36) are each supported on a pivot bearing (38) and have, at the end remote from the connection nipple (30), beyond pivot bearing (38), an actuating arm (42) which can be actuated, in order to close the retaining jaws (36), by a piston (44) subjected to the pressure of the medium.

The invention relates to a coupling for pressure lines, having a housing, which has a continuous conveying duct for a pressurised medium and can be connected by one end to a pressure source attached by the opposite end to a connection nipple, and having retaining jaws which are arranged around the mouth of the conveying duct opening into the connection nipple and which can be fixed by a locking mechanism in a position in which they engage around the connection nipple.
More particularly, the invention relates to a coupling for a lubricating line via which grease from a grease gun is pressed into a lubricating nipple.
Examples of couplings of this type are disclosed in WO2011/069172A1 and U.S. Pat. No. 2,578,517A.
The coupling may be connected directly to the output port of a grease gun or may be connected with the grease gun via a flexible tube or a rigid pipe and can be coupled to a lubricating nipple such that the lubrication grease can be pressed into the nipple. With increasing pressure of the lubricant, the risk increases that the retaining jaws yield and the coupling is detached from the nipple. For this reason, known couplings have a locking mechanism that can be operated manually and lock the retaining jaws in the closed position. This, however, makes the handling of the coupling cumbersome.
There are also known couplings wherein the retaining jaws are self-lockingly held in the closed position, so that they will not yield even under high pressure. In this case, however, it is difficult to detach the coupling from the nipple when the lubricating task has been accomplished.


Embodiments of the invention provide a magnetic disk drive and magnetic disk drive control method for unloading a head safely with a simple configuration when a positioning control signal cannot be detected due, for instance, to a seek error. In one embodiment, when a head cannot detect servo information prerecorded on a disk, a positioning control section resets and starts a time counting section, and switches to an unloading control section for causing the unloading control section to output a position control signal to a VCM driver. The time counting section counts tacho-pulses generated by a motor driver, and outputs time information. The unloading control section receives the time information from the time counting section. In accordance with the received time information, the unloading control section computes the position control signal that the positioning control section outputs to the VCM driver. In this instance, the unloading control section controls the VCM driver to provide such an electrical current profile that the drive current to be supplied to a VCM is small at an initial stage and large at a later stage.

The present invention relates to a magnetic disk drive that is capable of properly unloading a head when a head positioning control signal cannot be detected, and to a method for controlling such a magnetic disk drive.
A head load/unload mechanism is used in some conventional magnetic disk drives. If head positioning control cannot be exercised for some reason, such magnetic disk drives perform an unloading position to unload a head onto a ramp.
In the above unloading operation, a constant current for unloading was formerly supplied to a voice coil motor (VCM) to unload the head onto the ramp. In some cases, however, the head bounced off a stopper so that a disk was dented when the head was loaded again onto the disk.
FIG. 5 shows an example of the above head unloading operation. If a constant current is supplied to the VCM to unload the head 12 in a situation where positioning control cannot be exercised while the head 12 is at position A, which is over the disk 10 as indicated in FIG. 5, the head 12 moves over an unloading surface 16 of the ramp 14 and toward the stopper 18. The unloading surface 16 is sloped so that the head 12 needs to move up a slope when the head 12 begins to be unloaded from the disk 10 to the ramp 14. Therefore, the constant unloading current to be supplied to the VCM needs to be large enough for the head 12 to move up the slope. If the head 12 is positioned away from the ramp 14 when positioning control cannot be exercised, a high moving speed results when the head 12 reaches the ramp 14. The reason is that the acceleration time is increased due to electrical current application. Thus, the head 12 moves up the sloped unloading surface 16 at a high speed. Consequently, the speed remains high when the head 12 collides against the stopper 18 as indicated by arrow B in FIG. 5. Therefore, when the head 12, which is put in an unstable attitude due to collision, is loaded onto a landing zone D as indicated by arrow C, the head 12 may collide against the disk 10, thereby denting the disk 10.
To prevent the head 12 from colliding against the disk 10 as described above, a technology disclosed by Japanese Patent Laid-open No. 2001-143228 moves, when the power supply is shut off, the head to the ramp at a low speed by using a small current that is obtained by rectifying a counterelectromotive force, which is generated by a spindle motor, and then causes the head to move up the sloped ramp by supplying a relatively large current from a precharged capacitor. This reduces the speed at which the head collides against the stopper.

Magnetic disk drive and magnetic disk drive control

Hitachi Global Storage Technologies Netherlands B.V.


An ergonomic auto emergency tool for alternatively functioning as a flashlight, an illuminating distress signal, a sonic alarm, a tire depth gauge, a tire air pressure gauge, a seat belt cutter and a motor vehicle window glass breaker. The auto emergency tool includes a main portion and a projecting portion extending from a joining portion and being integral with the main portion, and defining a seat belt-receiving notch therebetween. A knife blade extends across the notch proximate the joining portion. An inner main portion-facing upper surface of the projecting portion is configured to facilitate the movement of the tool towards and through a seat belt, and the bottom outer surface of the projecting portion is curved for both easy handling and for enabling a firm grip when the tool is used to break window glass. The window-breaking mechanism includes a depressible plunger cover for releasing a spring-loaded impact member. A projecting portion and a main housing portion cooperate to define a seat belt receptacle. A blade cover is insertable into the seat belt receptacle. A blade cover includes a tire tread-depth gauge. The auto emergency tool further has a tire pressure gauge with a digital display. An optional visor clip is also provided for storing the tool on the visor of a motor vehicle. The visor clip has an alternate blade cover for attaching the tool to the visor.

1. Field of the Invention
This invention relates to handheld emergency tools, and in particular to small emergency tools to enable a person to escape from a motor vehicle, such as an automobile, when the motor vehicle is in an emergency situation, and a visor clip therefor.
2. Description of the Prior Art
There are many incidences where persons in a motor vehicle, such as an automobile, require assistance to escape from the motor vehicle quickly and safely. This could occur in the event the motor vehicle was involved in a collision with another motor vehicle or with some other object, became immersed in water, caught on fire and the like. In most motor vehicles, there are two obstacles for preventing easy escape from the vehicle; these are the windows of the vehicle and the seat belt which is used to hold an occupant in place. Furthermore, a person in distress from such a motor vehicle incident requires assistance in both finding a path to escape the vehicle and to emit a signal to possible rescuers. If an occupant is unable to open a window in the vehicle as a path of escape, it would be necessary to break the window in as short a period of time as possible while requiring limited strength and range of motion, particularly if the occupant is injured, fragile, weak, and in some instances having a little time or room to break the window. Also, there may be instances where an occupant is unable to open a locked seat belt apparatus, such as in the event the operating mechanism is inoperative possibly because of an accident, because the occupant is unable to reach the release mechanism for the seat belt, because obstacles impeding access to release the operating mechanism, because the operating mechanism is malfunctioning or for some other reason cannot release the seat belt.
Commonly owned U.S. Pat. No. 7,557,720, entitled "Personal Emergency Device," is directed to a personal emergency device which can be kept on a keyring and is useful in various emergency functions, such as those directed to emergency situations involving automobiles. This device has been found very useful because it is small and provides a device for cutting an automobile vehicle's seat belt webbing in the event the driver or passengers are unable to unfasten their seat belts, it includes a device for breaking tempered, unlaminated automobile side window glass by means of a spring-actuated pin having a sharp point that is driven into the glass to break it and which automatically resets for further use. The foregoing device also includes electronically operated items including a high beam and low beam LED flashlight, an emergency red LED light flasher, a thermometer, a digital tire gauge and an audible alarm. While the latter device, which is currently on the market and sold as a Swiss+Tech BodyGard® 7-in-1 Automobile Emergency Tool, its illumination could be brighter considering the emergency situation in which it could be involved, such as a warning signal and/or to illuminate a path of escape, and its battery life could advantageously be extended. Additionally, its ergonomics could be improved.
Another automobile emergency tool was marketed by the applicant under the name Swiss+Tech BodyGard® ESC 5-in-1 Automobile Emergency Tool. This was an ergonomic device which was small enough to be held on a keychain, and had a glass breaker, a seat belt cutter, a sonic alarm, an LED flashlight and an emergency red LED light flasher. Subsequently introduced to the market was a device entitled Swiss+Tech BodyGard® PTX Auto Emergency Tool. The latter tool is the subject of International Publication No. WO 2013/122604 A1. The latter device is an ergonomic auto emergency tool having a glass breaker, a seat belt cutter and an LED flashlight. The latter device is relatively small compared to the two auto emergency tools discussed above. Each of the foregoing products marketed by the applicant have a razor-sharp safety blade for cutting a seatbelt, and a blade cover slides in and out over the blade to protect the blade and to avoid unintentional cutting when the blade is not in use for cutting a seat belt. The foregoing BodyGard® 7-in-one Auto Emergency Tool has a sonic alarm, which is turned on and off by the pressing of a button. It can be deactivated by simply removing the user's hand from the button but keeps generating a warning signal for a period of time.
There are other similar devices which have serious setbacks. U.S. Pat. No. 5,657,543, entitled "Emergency Tool," is directed to a device which is large and bulky, and is for use by emergency personnel having a spring-loaded, trigger operated impact member for breaking glass in a vehicle. The device has an emergency glass-breaking tool, a pivotal knife blade, but no warning or alarm member. The device is fairly large, and would fill up a user's hand. Another known device is described in U.S. Pat. No. 5,952,916, entitled "Hammer Equipped Emergency Signal Device," having an LED for emitting a warning light, an alarm buzzer and a pair of percussion imparting members which must be swung as a hammer to break the glass. This device is large, requires space to operate and expensive for one to buy. Another device is shown in U.S. Pat. No. 6,418,628, which is allegedly small enough to be carried on a keychain, in a pocket or a purse and includes a spring-loaded glass breaker. It also includes a V-shaped razor blade for cutting a seat belt. This device does not have a light of any sort.
There are other devices known which are of general interest. Referring to U.S. Pat. No. 4,209,870, there is disclosed a handheld cleaning device having a cleaning section and an illuminating system for acting alternatively as a flashlight or as a beacon. An aiming post light is disclosed in U.S. Pat. No. 4,290,095. This light is used for artillery and mortar operations at night, and can be used to provide either steady light or a blinking light, and the blinking light could be red or green, which could be used to assist colorblind operators to distinguish between the two colors. An emergency flashlight is described in U.S. Pat. No. 7,033,042. This apparatus has a flashlight body with a battery storage unit and incorporates a hook member for supporting the flashlight on various objects, such as a belt or a handle ring of handbag. It also has a glass-cutting edge with a hammer piece which can be used to cut, strike and break glass and other debris during an emergency situation. None of the latter three devices are small enough to be easily held in a pocket, handbag or on a keyring.


In this invention an umbrella with a cover, preferably square or rectangular, is supported on a telescopic shaft by articulated ribs that extend from the shaft beneath the cover. The articulated ribs are connected to auxiliary ribs and both are controlled by guides and stabilizers that extend radially from a reciprocable transfer sleeve on the telescopic shaft and move the ribs and auxiliary ribs to fold the cover inside out as the transfer sleeve is lowered on the shaft, the shaft is shortened, and the umbrella is closed.

The following patents show the state of the art for reversible umbrellas as known to applicants:
U.S. Pat. No. 428,661 issued May 27, 1890 to Albin for UMBRELLA OR PARASOL FRAME;
U.S. Pat. No. 2,607,362 issued Aug. 19, 1952 to Evans for REVERSIBLE UMBRELLA;
U.S. Pat. No. 2,725,066 issued Nov. 29, 1955 to Estes et al. for REVERSIBLE UMBRELLA;
U.S. Pat. No. 2,788,792 issued Apr. 16, 1957 to Koller for WIND-RESISTANT REVERSIBLE UMBRELLA; and
U.S. Pat. No. 5,284,172 issued Feb. 8, 1994 to Teate, Jr. for REVERSING UMBRELLA APPARATUS.
Albin, Evans and Koller show reversible umbrellas supported on shafts of constant lengths.
Estes discloses several embodiments. The embodiment of FIGS. 1-3has a circular cover supported beneath ribs on a constant-length shaft.
The embodiment of FIGS. 4-7 has a circular flexible cover supported on braces connected to telescopic ribs on a constant-length shaft. The braces are also connected to a reciprocable hand-hold that is manipulated on the shaft to open the umbrella and close it with the cover turned inside out.
The embodiment of FIG. 8 in Estes has a square cover on a constant-length shaft. The square cover is turned inside out by ribs and braces externally of the cover as the umbrella is closed.
Estes' embodiment of FIGS. 9-14 has a circular cover supported on telescopic ribs extending radially from a reciprocable hand-hold on a telescopic shaft and on braces extending radially from a cap on top of the telescopic shaft. The cover is turned inside out as the umbrella is closed. The telescopic ribs undesirably increase the weight of the umbrella.
Teate discloses an umbrella with a tubular shaft including a collar with ribs mounted to the collar and each rib including a slide housing and a support rib. A cover is secured to the ribs. The slide is arranged in cooperation with the slide housings to reverse the arcuate orientation of the ribs and turn the ribs from a downward to an upward position.
An umbrella with a square cover has the advantage of stability, as noted by Estes, and also has the advantage of providing more protection in confined areas, as in getting in and out of a car. The advantages of umbrellas with telescopic shafts that shorten when the umbrella is closed are well known but most such umbrellas do not turn the cover inside out as the umbrella is closed.


A gas sensing mask and system which senses and indicates the presence or absence of a selected respired gas. The mask includes a non-porous housing that is sized to seat over the nose and mouth of a subject. The mask includes a fluid aperture that is coupled to a fluid source and a sensor mounting aperture formed in an intermediate portion of the housing. A gas sensor, which senses one or more selected gases respired by the subject, is directly mounted within the sensor mounting aperture. The gas sensor includes a calorimetric indicator which visually indicates the presence or absence of the respired gas.

The present invention generally relates to fluid delivery systems, and more particularly to fluid delivery systems that administer oxygen or other suitable gases to a patient.
Each year relatively large numbers of individuals suffer from some type of acute distress which requires treatment at hospitals or by emergency response personnel. Often times, in order to stabilize the individual during the distress period, it is necessary to supplement the individual's oxygen intake to facilitate the breathing of the individual. Once the patient is treated and stabilized, the patient may still require a supplemental oxygen supply. In such cases, it is important to monitor the breathing rate of the individual to ensure continuous respiration and proper oxygen uptake. Hence, if the acute distress reoccurs, which can result in difficulty or a complete cessation of breathing, the hospital clinicians or emergency response personnel can quickly recognize the situation and respond accordingly.
There presently exists several conventional practices for administering oxygen to facilitate breathing of a patient in distress. One practice includes the use of a looped cannula having a pair of stub-like portions which are placed within the nostrils of the patient. Oxygen is introduced to the patient through these stub-like portions. Typical drawbacks of using the cannula include irritation of the nose, which causes swelling and at times severe discomfort, particularly if the person is allergic to the long term presence of the cannula. Another drawback is that the cannula can become easily crimped, thus cutting off the oxygen supply to the patient. Further drawbacks include the relatively easy dislodgment of the cannula from the patient's nostrils.
A variety of oxygen masks have also been used to administer oxygen to the patient. The oxygen masks vary in type and construction depending upon the specific purpose or use of the mask. Conventional oxygen masks include a body, either resilient or rigid, that is sized to seat over the face of the patient. Oxygen is introduced to the patient through an oxygen inlet, and respired gases are vented from the mask interior through appropriately placed ventilation apertures.
Other conventional oxygen administering apparatuses include oxygen tents which substantially completely surround the patient's head. The oxygen tent includes a support structure that supports a resilient membrane (which forms an oxygen chamber) about the patient's head. Oxygen is supplied to the interior of the chamber by appropriately placed fluid conduits. A drawback of the oxygen tent is that a relatively significant portion of the oxygen can escape from the tent. Thus, the total amount of oxygen supplied to the patient is not readily determinable. Furthermore, the creation of a highly flammable environment about the patient's head exposes the patient to risk of injury.
The industry has also developed a number of carbon dioxide indicators which detect the presence of carbon dioxide in a gas mixture. These carbon dioxide detection apparatuses include a chemical compound that changes color in the presence of carbon dioxide. Other devices include pH sensitive dyes suspended in a gel substance, and gas analyzers which typically employ a light source to transmit light through a multi-layered sensor unit and a detector to receive and analyze the color changes of a pH sensitive indicator disposed in one or more of the layers. These devices are commonly used, however, in conjunction with endotrachial tubes to determine whether correct intubation procedures have been effected. Examples of such carbon dioxide indicators are shown and described in U.S. Pat. No. 4,728,499 of Fehder, U.S. Pat. No. 4,994,117 of Fehder, and U.S. Pat. No. 5,375,592 of Kirk et al.
A common drawback of the foregoing conventional oxygen-administering and endotracheal devices is that they generally do not monitor, over a period of time, the breathing or respiration of the patient.
Due to the foregoing and other shortcomings of prior art oxygen administering and gas detecting devices, it is thus an object of the present invention to provide a system for continuously monitoring the respiration of a patient.
It is another object of the invention to provide a relatively lightweight and relatively low cost gas-sensing device suitable for use in hospital and home care environments.
Still another object of the invention is to provide a system and apparatus that continuously detects changes in the respiratory rate of a subject wearing a gas delivery system.
Yet another object of the invention is to provide a system and apparatus that provides a visual indicator of the respiration of the patient.
Still yet another object of the invention is to provide apparatus that detects and displays or indicates the respiratory rate of the subject.
Another object of the invention is to provide a relatively reliable and inexpensive apparatus that monitors the breathing rate of the subject.
Other general and more specific objects of the invention will in part be obvious and will in part appear from the drawings and description which follow.

Beth Israel Deaconess Medical Center, Inc.


A system and method for concurrency control in high performance database systems. Generally includes receiving a database access request message from a transaction. Then, generating an element that corresponds to the access request message. The element type is that of a read element, commit element, validated element, or restart element. The element is then posted to a read-commit (RC) queue. If the element is a commit element, an intervening validation of the transaction is performed. Upon the transaction passing validation the requested database access is performed.

In recent years the Internet has grown so fast that E-businesses are becoming highly profitable. Internet database systems provide business information from which an unprecedented number of customers may access. With the drastic growth of Internet users, the demand for higher system throughput becomes urgent. Replicated database systems have attracted considerable attention due to their apparent advantages of improved data availability and system scalability. In a replicated database system, identical copies of data objects are kept in multiple geographically distributed sites to provide nearby customers with fast and easy accesses. The multiple copies of data objects also provide a much more reliable information service against system outages, which might otherwise cause severe losses in E-businesses, such as online stock trading systems. However, while the replication paradigm brings the benefit of quick response to read-only operations, it does cause new problems—the workload of updates in each site increases proportionally to the number of replicas of data objects. It has been discussed that the deadlock rate has a cubic growth versus the number of replicas. This implicates that two-phase locking, the most commonly used locking-based concurrency control method, cannot meet the increasing needs of high performance in today's Internet database systems such as online shopping systems, stock trading systems, etc.
The relative performance of three different approaches for concurrency control, i.e., blocking-based, immediate-restart, and optimistic, under a variety of modeling assumptions have been studied. In the blocking-based approach, transactions set read locks on objects that they read, then upgrade the read locks to write locks for the objects that they also write. When a lock request is denied, the requesting transaction is blocked. Wait-for-graph is used for deadlock detection. In the immediate-restart approach, transactions lock the objects in the same way as in the blocking-based approach, but they are aborted immediately when a lock request is denied. In the optimistic approach, transactions are allowed to be executed unhindered and are validated only after they have reached their commit points, but they are restarted if any object they read has been written by other committed transactions. The conclusion is that a concurrency control method that tends to conserve physical resources by blocking transactions, such as S2PL, out performs immediate-restart and optimistic methods for medium to high levels of resource utilization. In an environment of sufficient resources of CPUs and disks, an optimistic method is a better choice in terms both system throughput and transaction response time.
With the fast progress of technologies, the available resources may no longer be a bottleneck, e.g., CPU speed increases drastically and the costs of disks and CPUs are dropping quickly. Thus, optimistic approaches seem more promising than ever. It has been proposed that a hybrid two-phase concurrency control method be used wherein, in the first execution phase an optimistic concurrency control method is used, and in the restart phase a conservative 2PL is used. With such a method it was found that, statistically, transactions intend to access the same dataset as before, if they are restarted due to access conflicts. With the access invariance property, this method ensures, at most, one transaction re-execution. This eliminates the repeated restart problems in optimistic concurrency control methods and makes transaction response time more predictable.

Multiversion read-commit order concurrency control