A nonlinear site flow system (referred to herein as an “NLSF System”) includes a nonlinear site flow context development module that works in conjunction with Web session information captured by the NLSF System to develop a context of a user's session. In one embodiment, the context of a user's session refers to interpreting the context of a user's Web session history. A nonlinear site flow context development module detects nonlinear flow events and determines whether the user, by initiating a nonlinear site flow action, such as a recall operation, has created a new session state or returned to a past session state. The nonlinear site flow context development module can then correctly determine the actual user flow during a Web session and develop an accurate context of the user's session.

1. Field of the Invention
The present invention relates in general to the field of information processing, and more specifically to developing session context from nonlinear Web site flow information.
2. Description of the Related Art
The use of networks, particularly the Internet, by users continues to rise as technology and interesting destinations increase. World wide Web ("Web") sites continue to play an increasing role in the business models of many businesses. Sophisticated Web sites, such as many configuration Web sites, present a large number of navigation path options to a user, and, thus, a large amount of information about the user's activity and information presented to the user is potentially available for collection and analysis.
Historical information surrounding a user's Web site session can be very valuable information, particularly when attempting to understand the context of a user's Web session. However, reliably capturing this knowledge, recording it in a useful and accessible format, and properly interpreting nonlinear site flow events have proven elusive for conventional technology.
U.S. patent application Ser. No. 10/324,764, filed Dec. 20, 2002, and entitled "GENERATING CONTEXTUAL USER NETWORK SESSION HISTORY IN A DYNAMIC CONTENT ENVIRONMENT", inventors Daniel P. Karipides and Susumu Harada, (herein referred to as the "Karipides I Application") describes a Web system that includes a session recording and parsing system and process ("SRP System") that can capture a wide range of a user's session related information. In one embodiment, the SRP System includes two main components, data recording hooks and a parser. The SRP System includes a data recording hooks library that provides the ability to implement a dynamic, Web-based application and gather a wide-range of information about user's session activity. The SRP System parser analyzes the gathered and logged information from the data recording hooks and re-creates a session history, with a desired level of contextual detail, of every individual user's session. In one embodiment, the SRP System embodies a flexible design system that allows a designer to customize the type of information recorded so as to re-create the desired granularity of history. The Karipides I Application is incorporated herein by reference in its entirety.
Many Web sites, such as automotive configuration Web sites, include complex applications that require most pages to be dynamically generated. To support dynamic page generation, these Web sites usually store session state data for every session. The state will change as the user navigates through the site. Knowing the actual progression of state changes is important in recreating the true context of a user's session. For example, the true context of a user's session can be important in identifying quality user sessions as described, for example, in U.S. patent application Ser. No. 10/699,148, filed Oct. 31, 2003, and entitled "IDENTIFYING QUALITY USER SESSIONS AND DETERMINING PRODUCT DEMAND WITH HIGH RESOLUTION CAPABILITIES", inventor Daniel P. Karipides, (herein referred to as the "Karipides II Application") which is incorporated herein by reference in its entirety. It is also often useful to analyze as many user sessions as possible. Discarding ambiguous data from nonlinear site flow records can eliminate a significant amount of valuable data.
Most conventional Web browsers support "back", "forward", "refresh", new Web session initiating operations, and other recall operations that permit the user to arbitrarily return to previously-viewed pages. Correctly supporting recall operations can be problematic for Web sites as the Web site's current state is not necessarily the same as the state for the page to which the user is returning. To develop an accurate context of a user's session history, the Web site needs some way of recalling or reconstructing the user's state at any arbitrary page. Since this is a difficult problem to solve, most Web sites impose a linear site flow—even if the user tries to return to a page via a recall operation. Thus, an inaccurate or, at the very least, an ambiguous user history presents itself to a system attempting to develop user context from user session history.
FIG. 1 depicts a linear site flow 104 of a Web site 100. Initially, a Web server 102 displays Page 1 to a user as a result of a page request submitted via user's browser or other mechanism to Web server 102. The Web server 102 provides new Page 2 to the user's browser in response to a user New Page Request 1 action, such as selecting an embedded link in the currently displayed page. In response to New Page Request 2, the Web server provides a New Page 3 to the user's browser. The user next selects a back button of the browser. The Web server 102 considers the recalled page as a new Page 4 although New Page 4 is actually Page 2 again. The user next submits New Page Request 3, and the Web server 102 provides New Page 5 to the user, which is actually the fourth new page provided to the user's browser.
FIG. 2 depicts a nonlinear site flow 200 represented by a tree structure. Websites that do properly support reconstructing the user's state permit the user to have a nonlinear site flow like the tree structure depicted in FIG. 2. As in FIG. 1, the user begins with Page 1, submits New Page Request 1, and Web server 202 provides new Page 2 to the user's browser. After submitting New Page Request 2 and receiving new Page 3, the user selects the browser's back button, and Web server 202 provides previously viewed page 2 to the user. Thus, the Web server is aware that current state is actually the same as the former state when Page 2 was previously provided. From Page 2, the user requests new Page 4. However, many Web sites do not support recognition of nonlinear site flow. Furthermore, conventional technology does not support developing a contextual session record that accounts for nonlinear site flow.

Developing session context from nonlinear web site flow records


A system and method for inputting Chinese characters using Pinyin without requiring the entry of a delimiter key between Pinyin entries in a reduced keyboard is disclosed. The system searches for all possible single or multiple Pinyin spellings based on the entered Latin alphabets. Once the user has completed the inputting of the Pinyin spellings for desired Chinese phrase or characters, all possible matching phrases or characters are displayed on screen and off-screen due to screen size. The user then scrolls through a list of matching phrases or characters and selects the desired one by clicking.

1. Technical Field
This invention relates generally to Chinese input technology. More particularly, the invention relates to a system and method for disambiguating phonetic entry.
2. Description of the Prior Art
For many years, the keyboard size has been a major size-limiting factor in the efforts to design and manufacture small portable computers because if standard typewriter-size keys are used, a portable computer must be at least as large as the keyboard. Although a variety of miniaturized keyboards have been used on portable computers, they have been found too small to be easily or quickly manipulated by a regular user.
Incorporating a full-size keyboard in a portable computer also hinders true portable use of the computer. Most portable computers cannot be operated without placing the computer on a substantially flat work surface to allow the user to type with both hands. The user cannot easily use a portable computer while standing or moving. In the latest generation of small portable computers, called Personal Digital Assistants (PDAs) or palm-sized computers, manufacturers have attempted to address this problem by incorporating handwriting recognition software in the device. Users may directly enter text by writing on a touch-sensitive panel or screen. This handwritten text is then converted by the recognition software into digital data. Unfortunately, in addition to the fact that printing or writing with a pen is in general slower than typing, the accuracy and speed of the handwriting recognition software has to date been less than satisfactory. In the case of Chinese language, with its large number of complex characters, the problem becomes especially difficult. To make matters worse, today's handheld computing devices which require text input are becoming smaller still. Recent advances in two-way paging, cellular telephones, and other portable wireless technologies have led to a demand for small and portable two-way messaging systems, and especially for systems which can both send and receive electronic mail ("e-mail").
Pinyin input method is one of the most commonly used Chinese character input method based on Pinyin, the official system of sounds forming syllables for Chinese language which was introduced in 1958 by the People's Republic of China. It is supplementary to the 5,000-year-old traditional Chinese writing system. Pinyin is used in many different ways. For examples: it is used as a pronunciation tool for language learners; it is used in index systems; and it is used for inputting Chinese characters into a computer. The Pinyin system adopts the standard Latin alphabets and takes the traditional Chinese analysis of the Chinese syllable into initials, finals (ending sounds) and tones.
Mandarin Chinese has consonant sounds that are found in most of the languages. For example, b, p, m, f, d, t, n, l, g, k, h are quite close to English. Other initial sounds, such as retroflex sounds zh, ch, sh and r, palatal sounds j, q and x, as well as dental sounds z, c and s, are different from English or Latin pronunciation. Table 1 lists all initial sounds according to the Pinyin system.
TABLE 1Initial SoundsInitial SoundPronunciation sampleNoteGroup I: Same pronunciation as in EnglishMManNNoLLetterFFromSSunWWomanYYesGroup II: Slightly Different from English PronunciationPPunuse a strong puff of breathKColause a strong puff of breathTTongueuse a strong puff of breathBBumno puff of breathDDungno puff of breathGGoodno puff of breathHHotslightly more aspirated than inEnglishGroup III: Different from English PronunciationZHJewelerCHAs in ZH but with a strong puff ofbreathSHShoeRRunCLike "ts" in "it's high", but with astrong puff of breathJJeffQClose to "ch" in "Cheese"XClose to "sh" in "sheep"
The finals connect with the initial sounds to create a Pinyin syllable which corresponds to a Chinese character (zi: _). A Chinese phrase (ci: _) usually consists of two or more Chinese characters. Table 2 lists all the final sounds according to the Pinyin system and Table 3 gives some examples illustrating the combination of initials and finals.
TABLE 2Final (ending) SoundsFinal SoundPronunciation sampleaAs in fatheranLike the sounds of "Anne"angLike the sound "an" with addition of "g"aiAs in "high"aoAs in "how"arAs in "bar"oLike "aw"ouLike the "ow" in "low"ongLike the "ung" in "jungle" with a slight "oo" soundeSounds like "uh"enLike the "un" in "under"engLike the "ung" in "lung"eiLike the "ei" in "eight"erLike the "er" in "herd"iLike the "i" in machineinAs in "bin"ingLike "sing"uLike the "oo" in "loop"unAs in "fun"
TABLE 3Putting Initials and Final (ending) TogetherPinyinPronunciation sampleNiLike "knee"HaoLike "how" with a little more aspirationDongLike "doong"QiLike "Chee"GongLike "Gung"TaiLike "Tie"JiLike "Gee"QuanLike "Chwan"
Each Pinyin pronunciation has one of the five tones (four pitched tones and a "toneless" tone) of Mandarin Chinese. A tone is important to the meaning of the word. The reason for having these tones is probably that Chinese language has very few possible syllables—approximately 400—while English has about 12,000. For this reason, there may be more homophonic words, i.e. words with the same sound expressing different meanings, in Chinese than in most other languages. Apparently tones help the relatively small number of syllables to multiply and thereby alleviate but not completely solve the problem. There is no paralleling concept of the tones in English. In English, an incorrect inflection of a sentence can render the sentence difficult to understand. But in Chinese an incorrect intonation of a single word can completely change its meaning. For example, the syllable "da" may represents several characters such as _ in first tone (da1) meaning "to hang over something", _ in second tone (da2) meaning "to answer", _ in third tone (da3) meaning "to hit", and _ in fourth tone (da4) meaning "big". The numbers after each of the syllables indicates the tones. The tones are also indicated by marks such as d_da_d_da_. Table 4 shows a description of five tones for the syllable "da".
TABLE 4Five TonesToneMarkDescription1std—High and level2ndda—Starts medium in tone, then rises to the top3rdd—Starts low, dips to the bottom, then rises toward the top4thda—Starts at the top, then falls sharp and strong to the bottomNeutraldaFlat, with no emphasis
To enter a Chinese character using the Pinyin system, the user selects English letters corresponding to the character's Pinyin spelling. For example, on a standard QWERTY keyboard, when the user wants a Chinese character with a Pinyin of "ni", he needs to press the "N" key and then the "I" key. After the "N" key and the "I" key are pressed, a list of Chinese characters associated with the Pinyin spelling "NI" is displayed. Then, the user selects the intended character from the list. This method is hereby referred as the basic Pinyin input method.
In a reduced keyboard system, such as one shown in FIG. 1, each key is associated with more than one letters of the Latin alphabet corresponding to each Pinyin syllable as shown in Tables 1 and 2. Thus a disambiguating method is needed for determining the correct Pinyin spellings that correspond to the input keystroke sequence.
A number of suggested approaches for determining the correct character sequence that corresponds to an ambiguous keystroke sequence are summarized in the article "Probabilistic Character Disambiguation for Reduced Keyboards Using Small Text Samples" by John L. Arnott and Muhammad Y. Javad (hereinafter as Arnott), which was published in the Journal of the International Society for Augmentative and Alternative Communication. Arnott notes that the majority of disambiguation approaches employ known statistics of character sequences in the relevant language to resolve character ambiguity in a given context. That is, existing disambiguating systems statistically analyze ambiguous keystroke groupings as they are being entered by a user to determine the appropriate interpretation of the keystrokes. Arnott also notes that several disambiguating systems have attempted to use word level disambiguation to decode text from a reduced keyboard. Word level disambiguation processes complete words by comparing the entire sequence of received keystrokes with possible matches in a dictionary after the receipt of an unambiguous character signifying the end of the word. Arnott points out several disadvantages of word-level disambiguation. For example, word level disambiguation often fails to decode a word correctly due to the limitations in identifying unusual words and the inability to decode words that are not contained in the dictionary. Because of the decoding limitations, word level disambiguation does not give error-free decoding of unconstrained English text with an efficiency of one keystroke per character. Arnott thus concentrates on character level disambiguation rather than word level disambiguation, and indicates that character level disambiguation appears to be the most promising disambiguation technique.
Still another suggested approach is disclosed in a textbook entitled Principles of Computer Speech, which was authored by I. El. Witten and published by Academic Press in 1982 (hereinafter as Witten). Witten discusses a system for reducing ambiguity from text entered using a telephone touch pad. Witten recognizes that for approximately 92% of the words in a 24,500 word English dictionary, no ambiguity arises when comparing the keystroke sequence with the dictionary. When ambiguities do arise, however, Witten notes that they must be resolved interactively by the system presenting the ambiguity to the user and asking the user to make a selection among the list of ambiguous entries. The user must therefore respond to the system's prediction at the end of each word. Such a response slows the efficiency of the system and increases the number of keystrokes required to enter a given segment of text.
Disambiguating an ambiguous keystroke sequence continues to be a challenging problem. As noted in the publications discussed above, existing solutions that minimize the number of keystrokes required to enter a segment of text have failed to achieve the necessary efficiencies to be acceptable for use in a portable computer. It would therefore be desirable to develop a disambiguating system that resolves the ambiguity of entered keystrokes while minimizing the total number of keystrokes required, within the context of a simple and easy to understand user interface. Such a system would thereby maximize the efficiency of text entry.
An effective reduced keyboard input system for Chinese language must satisfy all of the following criteria. First, the input method must be easy for a native speaker to understand and learn to use. Second, the system must tend to minimize the number of keystrokes required to enter text in order to enhance the efficiency of the reduced keyboard system. Third, the system must reduce the cognitive load on the user by reducing the amount of attention and decision-making required during the input process. Fourth, the approach should minimize the amount of memory and processing resources needed to implement a practical system.
The basic Pinyin method can be applied to a reduced keyboard input system when combined with a non-ambiguous method of input Latin alphabets such as the multi-tap method. All non-ambiguous method, however, requires lots of key strokes, which is especially burdensome when combined with the basic Pinyin method. Thus it is preferable to combine the basic Pinyin method with a disambiguating system. One approach is developed to disambiguate only one Pinyin syllable at one time by requiring the user to select a delimiter key, such as key 1 or key 0, between Pinyin spellings that correspond to multiple Chinese characters in commonly known Chinese phrases (_, i.e. a word with more than one character). The selection of the delimiter key instructs the processor to search for Pinyin syllables that match the input sequence and for Chinese characters associated with the first Pinyin syllable which may be selected by default. As shown in FIG. 1, the user is trying to input the Chinese characters associated with the Pinyin spellings NI and Y. To do this, the user would first select the '6' key 16, then the '4' key 14. In order to instruct the processor to perform a search for a syllable matching the keys entered, the user then selects the delimiter key 10 and finally the '9' key 19. Because this process requires a delimiter key depression between commonly linked multiple Chinese character words, time is wasted.
Another significant challenge facing an application of word-level disambiguation is how to successfully implement it on types of hardware platforms on which its use is most advantageous, such as two-way pagers, cellular telephones, and other hand-held wireless communications devices. These systems are battery powered, and consequently are designed to be as frugal as possible in hardware design and resource utilization. Applications designed to run on such systems must minimize both processor bandwidth utilization and memory requirements. These two factors tend in general to be inversely related. Since word-level disambiguation systems require a large database of words to function, and must respond quickly to input keystrokes to provide a satisfactory user interface, it would be a great advantage to be able to compress the required database without significantly impacting the processing time required to utilize it. In the case of Chinese language, additional information must be included in the database to support the conversion of sequences of Pinyin syllables to the Chinese phrases intended by the user.
Another challenge facing any application of word-level disambiguation is how to provide sufficient feedback to the user about the keystrokes being input. With an ordinary typewriter or word processor, each keystroke represents a unique character which can be displayed to the user as soon as it is entered. However, with word-level disambiguation this is often not possible because each keystroke represents multiple letters in a Pinyin spelling and any sequence of keystrokes may match multiple spellings or partial spellings. It would therefore be desirable to develop a disambiguating system that minimizes the ambiguity of entered keystrokes and also maximizes the efficiency with which the user can resolve any ambiguity which does arise during text entry. One way to increase the user's efficiency is to provide appropriate feedback following each keystroke, which includes displaying the most likely word spelling following each keystroke, and in cases where the current keystroke sequence does not correspond to a completed word, displaying the most likely stem of a yet uncompleted word.

System and method for disambiguating phonetic input


A guidewire for backloading and inserting a percutaneous pump affixed to a cannula includes a proximal section made of a first material, with a first diameter, a rounded proximal end, and a distal end. The guidewire also includes a distal section made of a second material, with a second diameter which is greater than the first diameter, a distal end, and a proximal end abutting the distal end of the proximal section. The first material of the proximal section is selected to be softer than a material of the percutaneous pump to reduce damage to the pump during backloading. The distal section of the guidewire is configured to be stiffer than the proximal section to insert the percutaneous pump in a desired location without damaging the guidewire.

A blood pump, such as a percutaneous intracardiac blood pump assembly, is introduced in the heart to deliver blood from the heart into an artery, such as the pulmonary artery. When deployed in the heart, a blood pump assembly pulls blood from the left ventricle of the heart and expels blood into the aorta, or pulls blood from the right ventricle and expels blood into the pulmonary artery, through a cannula. Blood pump assemblies are introduced surgically or percutaneously during a cardiac procedure through the vascular system. In one common approach, pump assemblies are inserted by a catheterization procedure through the femoral artery using a guidewire.
An introducer is inserted into the femoral artery through an arteriotomy to create an insertion path. A placement guidewire is then advanced distal end first through the sheath into the artery. Once the guidewire has been inserted into the artery, the pump assembly, including a pump and a cannula, is backloaded onto the proximal end of the guidewire and pushed along the guidewire and into the patient. The pump assembly may then be used in conjunction with a catheter.
As defined herein, backloading involves inserting the proximal end of the guidewire, which remains outside the patient, into the distal end of the catheter and then advancing the catheter distally over the wire. Backloading the pump assembly allows the guidewire to remain in position within the patient while different size catheters or sheaths are inserted and removed during the course of a procedure. But the cannula of the pump assembly can have a tortuous shape, or the cannula can be stiff. In these cases, the guidewire may not be stiff enough to allow backloading of the pump through to the pulmonary valve, and as a result the cannula of the pump may displace the guidewire out of the pulmonary valve. For example, for systems delivering blood from the inferior vena cava to an opening in the pulmonary artery, the cannula of the pump may be a 3D shape with two "S" turns in different planes. This can make backloading and insertion of the pump assembly into a patient particularly difficult.

This patent is subject to a terminal disclaimer.


A fuel tank cap structure with reduced casing body weight and improved dimensional accuracy is disclosed. The casing body of the fuel tank cap has a valve chamber, in which a positive pressure valve and a negative pressure valve are received. The casing body includes an outer tubular body and a valve chamber-forming member located inside the outer tubular body. The outer tubular body is joined with the valve chamber-forming member via a horizontal joint member and vertical horizontal members, which are arranged in a hollow portion.

1. Field of the Invention
The present invention relates to a cap of a fuel tank with a pressure control valve for controlling pressure in the fuel tank.
2. Description of the Related Art
One known example of fuel tank caps is disclosed in JAPANESE UTILITY PATENT PUBLICATION GAZETTE No. 6-88606. FIG. 38 is a sectional view illustrating a fuel tank cap 300. As shown in FIG. 38, the fuel tank cap 300 includes a plastic casing body 302 screwed to a filler neck FN of a fuel tank (not shown), a cover member 330 attached to the casing body 302, and a negative pressure valve 340 received in a valve chamber 304 of the casing body 302 for controlling pressure in the fuel tank. The negative pressure valve 340 includes a rubber valve body 342, a valve supporting member 346 with a fitting aperture 346a for supporting the valve body 342, and a spring 348 for pressing the valve body 342. When the differential pressure between the tank pressure and the atmospheric pressure applied to the valve body 342 increases to or above a predetermined level, the negative pressure valve 340 opens to make the tank pressure approach atmospheric pressure.
The casing body 302 has threads 302a formed on the circumference thereof to be screwed to the filler neck FN. The casing body 302 is thus required to have high mechanical strength. The casing body 302 has a valve chamber 304 in which the negative pressure valve 340 is received. High dimensional accuracy is required to enhance the sealing characteristics of the fuel cap. If the wall thickness of the casing body were increased to enhance the mechanical strength of the casing body 302, then sink marks are formed in injection molding which deteriorate the dimensional accuracy.


A method of making a molten sodium battery is disclosed. A first metallic interconnect frame having a first interconnect vent hole is provided. A second metallic interconnect frame having a second interconnect vent hole is also provided. An electrolyte plate having a cathode vent hole and an anode vent hole is interposed between the metallic interconnect frames. The metallic interconnect frames and the electrolyte plate are sealed thereby forming gaseous communication between an anode chamber through the anode vent hole and gaseous communication between a cathode chamber through the cathode vent hole.

Environmental concerns over the use of fossil fuels and their resource constraints have spurred increasing use of energy generated from renewable sources such as wind and solar. Despite the abundance and ready availability, power generated by solar and wind resources are variable and uncontrolled. An effective approach to smooth out the intermittency is to use electrical energy storage (EES), storing excessive energy and releasing it when needed. The EES technologies are also demanded to improve the reliability and security of future electrical grids. Among various EES technologies, electrochemical energy storage systems or batteries are capable of reversibly storing and releasing electrical energy without involving "Carnot" cycles. One such technology is based on a β″-Al2O3 solid electrolyte (BASE) and this type of electrochemical device is often referred as Na-beta batteries (NBBs).
The high round-trip efficiency, high energy density and capability of energy storage for a duration of hours has led to an increased interest in NBB technologies for renewable storage and utility applications, as well as for clean, efficient vehicles. However. NBBs are batteries typically constructed on thick tubular electrolytes and operate at relatively high temperatures. Thus, while having promise from a theoretical perspective, these NBBs have a number of disadvantages, such as high capital cost and performance/safety issues, that have limited market penetration of the technology,
One common cathode of NBBs is molten sulfur. This type of battery is known as sodium-sulfur (Na—S) battery. Na—S technologies for utility energy storage have also been developed. As an alternative to the molten S/Na2Sx cathode, porous Ni/NiCl2 structures impregnated with molten NaAlCl4 have been used in the so-called ZEBRA hatter.
The β″-Al2O3 solid electrolyte (BASE) belongs to beta-alumina group, which is characterized by structures composed of alternating closely-packed slabs and loosely-packed layers. The loosely-packed layers contain mobile sodium ions and are called conduction planes or slabs, in which the sodium ions are free to move under an electric field. The closely-packed slabs are layers of oxygen ions with aluminum ions sitting in both octahedral and tetrahedral interstices. These layers are referred as the spinel block, which is bonded to two adjacent spinet blocks via conduction planes or slabs. The sodium ions diffuse exclusively within the conduction layers perpendicular to the c axis. There are two distinct crystal structures in the group: β—Al2O3 (hexagonal; P63/mmc; αo=0.559 nm, co=2.261 nm) and β″—Al2O3 (rhombohedral; R3m; αo=0.560 nm, co=3.395 nm). The differ in chemical stoichiometry and stacking sequence of oxygen ions across the conduction layer and sodium-ion conductivity. β″—Al2O3 exhibits a higher sodium ionic conductivity (typically 0.2˜0.4 S cm−1 at 300° C.) and is the preferred phase for sodium battery electrolyte applications,
The tubular design has been the dominate geometry of NBBs since the inception. However, the tubular design has many drawbacks. First, a tubular design requires a relatively thick cathode and smaller active surface area for a given cell volume, which limits power and energy densities. Secondly, the thicker electrolyte (>1 mm) typically employed in tubular designs also limits the high power characteristics. The tubular design complicates the interconnect between single cells and also impacts the overall cell packing efficiency. Finally, for metal halide sodium batteries they are typically manufactured by providing the sodium on the cathode side as a salt, such as NaCl. The sodium is then separated from the chloride and transferred to the anode side during the charge/discharge process. This method of manufacture limits the charge density of the resultant battery. Also, during the charge/discharge cycle, sodium battery electrode compartment undergoes volumetric changes. These changes along with the vapor pressure of molten sodium metal and other gases can create a differential pressure within the cell. This also limits the charge density of the resulting battery, because too much pressure can rupture the electrolyte.
The present invention is designed to overcome these drawbacks.


Field-flattening strands may be added to and arbitrarily positioned within a field-flattening shell to create a waveguide that supports a patterned, flattened mode. Patterning does not alter the effective index or flattened nature of the mode, but does alter the characteristics of other modes. Compared to a telecom fiber, a hexagonal pattern of strands allows for a three-fold increase in the flattened mode's area without reducing the separation between its effective index and that of its bend-coupled mode. Hexagonal strand and shell elements prove to be a reasonable approximation, and, thus, to be of practical benefit vis-à-vis fabrication, to those of circular cross section. Patterned flattened modes offer a new and valuable path to power scaling.

1. Field of the Invention
The present invention relates to waveguides that propagate light at multiple, yet discrete speeds—equivalently, multiple discrete transverse modes—and that transport telecommunications signals, generate or amplify light, transport electromagnetic power, or are used for decorative or display purposes.
2. Description of Related Art
For optical fiber lasers to scale to higher energies and powers, the fibers themselves must have greater cross-sectional areas in order to withstand those energies and powers. However, merely scaling the dimensions of optical fibers leads to systematic problems that can compromise the performance and utility of the very systems that they are intended to service. As an example, fibers of large cross sections can support a large number of spatial modes that scale with the square of the fiber diameter relative to the wavelength. Fibers with many higher-order modes result in "hot spots" in the guided optical beam, which can result in catastrophic optical damage and undesirable nonlinear optical effects. In addition, fibers that support a large number of modes can limit the bandwidth (e.g., the data rate) of communication information. This follows since each mode propagates at a slightly different speed through the fiber, with the result that a short optical pulse will temporally spread over a given length of fiber.
Several approaches to increase the effective cross-sectional area of a fiber have been discussed in the literature. In one case, the fiber is designed to maintain but a single spatial mode as the physical size of the fiber increases, thereby increasing the effective cross-sectional area of the fiber. Although functional in many applications, these large-area single-mode fibers are susceptible to bending losses. In another approach, a fiber can be designed to support many higher-order modes (HOM). These HOM fibers, can, in fact, result in a larger effective cross-sectional area, but, circularly symmetric versions suffer from hot spots that reduce the thresholds for nonlinear artifacts and damage.
The present invention circumvents these limitations. Using so-called field-flattening designs, a well tailored, single-spatial-mode HOM fiber can be realized, without the deleterious effects of hot spots. Moreover, by enabling asymmetric structures with azimuthal modal patterns, the resultant fibers can be designed to realize large effective cross-sectional areas, with a spatially uniform mode, as well as to realize polarization-maintaining fibers. Moreover, by fabricating the fiber with a helical (twisted) preform, the resultant HOM, field-flattened fiber can provide an output field with a specific optical angular momentum state, which has myriad potential applications. In general, the fiber structures described herein can be fabricated to possess optical gain regions, with potential application to long-haul communication links, and high-power beam delivery systems for commercial and defense needs. An added feature is that these amplifying fibers can be designed using uniform gain regions, so that the need for non-uniform doping regions can be obviated.
As noted above, a major problem currently exists when scaling fibers (and waveguides) to support higher-order spatial modes, namely, that these structures can result in hot spots, which can lead to optical damage as well as undesirable nonlinear optical artifacts. In addition, existing scaling design rules can result in fibers with multiple spatial optical modes, each of which possess differing propagation speeds (i.e., modal dispersion). In conventional fibers, this state of affairs can lead to undesirable mode mixing, which can also limit the data rate and/or bandwidth in long-haul optical communication links.
Specifically, in the latter case, as one scales up the mode area in conventional fibers, the modal separation decreases in inverse proportion. This decrease in mode separation is undesirable in that it exacerbates modal mixing, which, as noted above, adversely affects the performance of fibers for beam delivery and communication purposes, among others. Moreover, as the fiber scales in size, the presence of additional modes makes it more and more difficult to launch a beam into a single, desired guided mode without exciting undesirable neighboring modes.
Conventional waveguides have other shortcomings as well. While it is known that the high order modes of circularly symmetric waveguides have larger modal separations than the low order modes of these guides, the high order modes suffer from on-axis "hot spots" which may limit the power or energy those modes can carry, and this detriment may outweigh their modal separation benefit. Specifically, these spatial intensity peaks can result in deleterious nonlinear propagation artifacts, which can induce power or energy to couple from a single desired HOM into other modes, degrading the quality of the beam emitted by the waveguide. That is, the diffraction-limited spot size increases, with the result that the minimal focal size of the beam increases. In addition, as the number of spatial modes increases, undesirable optical hot spots appear in the output beam. Conventional waveguides tend to have a packing efficiency of roughly 50%. It is desirable that waveguides have packing efficiency that approaches 100%. This latter benefit is enjoyed by the now well-known waveguides whose fundamental modes are power-flattened. However, those latter waveguides cannot practically achieve the large modal areas necessary for next generation applications, which, using the teachings herein, are now realizable, using the design rules described herein to realize fibers with field-flattened, single HOM configurations.

Waveguides having patterned, flattened modes

Lawrence Livermore National Security, LLC


A method for plugging and sealing subsurface formations using alkaline nanosilica dispersion and a delayed activation chemistry is disclosed. In accordance with one embodiment of the present disclosure, the method includes introducing a mixture with a first pH into the subsurface formation. The mixture comprises an aqueous solution, an alkaline nanosilica dispersion and a water-soluble hydrolyzable compound. The method further includes allowing the water-soluble hydrolyzable compound to hydrolyze in the subsurface formation to form an acid at 70° C. or greater, thereby acidizing the mixture to a reduced second pH and causing the alkaline nanosilica dispersion to gel into a solid and seal the subsurface formation. A composition for sealing a subsurface formation is also disclosed. The composition includes an aqueous mixture including water, an alkaline nanosilica dispersion, and a water-soluble hydrolyzable compound.

Excessive water production greatly affects the economic life of producing wells. High water cut, such as a water cut of greater than 50%, largely affects the economic life of producing wells and is also responsible for many oilfield-related damage mechanisms, such as scale deposition, fines migration, asphaltene precipitation, and corrosion. In such water production instances, methods and compositions for plugging and sealing subsurface zones that lead to high water cut in wells can be utilized to decrease the water cut.

Method and composition for sealing a subsurface formation


A display apparatus divides each frame period of an input image signal into a plurality of subframes and selects the subframes according to a gray-scale level of the input signal, to display a gray-scale image. The display apparatus alternately employs two sets of tables having different gray-scale-level input/output characteristics, to move locations to cause false contours frame by frame, thereby minimizing false contours.

1. Field of the Invention
The present invention relates to a display apparatus, and particularly, to a display apparatus such as a plasma display panel (hereinafter referred to as PDP) that divides a frame period of an image signal into a plurality of subframes and selectively activates the subframes to display gray-scale images.
2. Description of Related Art
The PDP drives each pixel in a binary mode or an ON/OFF mode. To display gray-scale images, the PDP divides a frame period (16.7 ms) of an image signal into subframes having different light emitting periods, respectively. The subframes are selectively driven according to a gray-scale level to display, so that a human eye may observe a gray-scale image due to a visual integration effect. The display apparatus employing the in-frame time division displaying method is disclosed in, for example, Japanese Unexamined Patent Application Publication No. Hei-7-271325.
FIG. 1 is a block diagram showing a display apparatus according to a related art. An image signal to be displayed is supplied to an image processor 1. The image processor 1 conducts image processes including error diffusion, dithering, and inverse gamma correction. The image signal processed by the image processor 1 is transferred to a subframe coordinator 2, which converts the image signal into subframes to drive corresponding red (R), green (G), and blue (B) pixels. At this time, the subframe coordinator 2 refers to a coding table 4 and a weighting table 3 stored in an external storage device. The weighting table 3 is related to the coding table 4 and indicates the number of pulses generated in each subframe to determine the brightness of the subframe.
The signal processed by the subframe coordinator 2 is transferred to a subframe processor 5. The subframe processor temporarily stores the signal, reads a subframe at the display timing thereof, sends a control signal to a drive pulse generator 6, and provides an address electrode driver 7 with pixel data. The drive pulse generator 6 supplies drive pulses to an X-electrode driver 8 and a Y-electrode driver 9, to start sustain discharge and activate pixels selected by the address electrode driver 7. As a result, the selected pixels are activated on a plasma display panel (PDP) 10. These operations are conducted subframe by subframe.
FIG. 2 shows an example of a subframe structure used to display a gray-scale image according to the related art. In FIG. 2, an ordinate indicates display lines Y1 to Yn and an abscissa indicates time. To realize 256 (8-bit) gray-scale levels, the example of FIG. 2 divides a frame into eight subframes SF1 to SF8 having different brightness weights. An LSB (least significant bit) to an MSB (most significant bit) of 8-bit image data are sequentially assigned to the subframes. Namely, the related art divides a frame into M subframes, selects subframes according to a gray-scale level of image data, and displays a gray-scale level of the "M"th power of 2 on the PDP 10, so that a viewer may see a gray-scale image on the PDP 10 due to a visual integration effect.
Each subframe consists of a reset period, an addressing period, and a sustain discharge period. The addressing period is a period to conduct a sequential line-by-line write operation. In FIG. 2, the sustain discharge periods are depicted with patterns and have different lengths from subframe to subframe. This is because each subframe has an individual brightness weight that determines the number of sustain pulses to be generated during the sustain discharge period of the subframe. The weights, i.e., the numbers of pulses generated during the sustain discharge periods of the subframes SF1 to SF8 are 1, 2, 4, 8, 16, 32, 64, and 128, respectively. To increase the brightness of light emission, the numbers of pulses are multiplied by N (a natural number).
The number of subframes may differ depending on display apparatuses. The PDP usually employs 10 to 12 subframes depending on the reset, addressing, and sustain discharge periods to be included in a frame period.
It is known that the display apparatus employing subframes to display gray-scale images shows false contours when displaying dynamic images. The false contours displayed on dynamic images will be explained.
FIG. 3 shows adjacent pixels displaying gray-scale levels of 127 and 128 on the PDP. In FIG. 3, a vertical direction indicates the pixels displaying the gray-scale levels of 127 and 128, and a horizontal direction indicates time. Subframes depicted with patterns are those selected to emit light. In this example, there are eight subframes SF1 to SF8 that are weighted by 1, 2, 4, 8, 16, 32, 64, and 128, respectively.
For the pixel to display the gray-scale level of 127, the subframes SF1, SF2, SF3, SF4, SF5, SF6, and SF7 are driven, so that the total weight of 127 thereof provides the gray-scale level of 127. On the other hand, for the pixel to display the gray-scale level of 128, only the subframe SF8 is driven, so that the weight of 128 thereof provides the gray-scale level of 128.
If a still image is displayed on the PDP at this time, a line of sight of a viewer is immobile. Namely, the line of sight does not move to the next pixel during integration of the weights of the subframes. In this case, the image is correctly viewed, and no false contour appears. If a dynamic image is displayed on the PDP at the time, a line of sight of the viewer moves according to the movement of the image. Namely, the line of sight moves to the next pixel before the weights of the subframes of the first pixel are integrated. Then, the viewer sees a false contour due to the visual integration effect of the eyes.
In FIG. 3, the pixels to display the gray-scale levels of 127 and 128 are adjacent to each other. If a dynamic image moves upwardly and if the eyes of the viewer move from one pixel to another at a speed within a visual integration time, a line of sight of the viewer will be a line "a" shown in FIG. 3. In this case, the viewer sees a black color because there are no subframes to emit light. If the image moves downwardly, the eyes of the viewer will move along a line "b". In this case, the subframes SF1 to SF8 are driven to emit light and their brightness is integrated, so that the viewer sees the total weight of 256, i.e., a gray-scale level of 256. In both cases, the pixels display the gray-scale levels of 127 and 128, respectively. However, the viewer sees a false white or black stripe.
This is a phenomenon called a dynamic image false contour. The phenomenon is specific to the display apparatus employing the in-frame time division displaying method and deteriorates image quality. The phenomenon, therefore, must be eliminated.
To solve the problem, there is a related art that employs two kinds of coding to realize different gray-scale levels with subframes. This related art displays 256 gray-scale levels by averaging the two kinds of coding. This technique is disclosed in, for example, Japanese Unexamined Patent Publication No. 2003-66892. The related art finds first and second gray-scale levels whose average is equal to a given gray-scale level, forms a light emission pattern A of subframes according to the first gray-scale level and a light emission pattern B of subframes according to the second gray-scale level, and alternates the light emission patterns A and B frame by frame.
This related art, however, involves some gray-scale levels each selecting the same subframes in both the light emission patterns A and B to unavoidably cause false contours.


A method, apparatus and computer readable medium for managing recording medium defects and a defect managed recording medium. The recording medium includes a spare area in which a replacement area, which is a substitute for a defective area of the recording medium, is formed, and a temporary defect management area in which temporary management information that specifies the defective area and the corresponding replacement area is recorded, wherein position information and state information regarding the defective area are recorded in the replacement area. Accordingly, it is possible to restore defect information even if recording medium defect management on the recording medium ended abnormally.

1. Field of the Invention
The present invention relates to defect management for recording media, and more particularly, to a method, apparatus, and computer readable medium for performing management of defects of a recording medium even when defect management of the recording medium is abnormally terminated, and a defect managed recording medium obtained using the same method, apparatus, and computer readable medium.
2. Description of the Related Art
Defect management includes a process of rewriting data stored in a defective area of a user data area of a recording medium in a new portion of the user data area, thereby compensating for data loss caused by the defective area. In general, defect management is performed using linear replacement or slipping replacement. In linear replacement, data stored in the defective area of the user data area is recorded in a spare data area having no defects. In slipping replacement, the defective area of the user data area is skipped and the next available area of the user data area having no defects is used.
Both linear replacement and slipping replacement are, however, applicable only to recording media such as a DVD-RAM/RW discs, on which data can be repeatedly written and recording can be performed using a random access method. It is difficult to perform linear replacement and slipping replacement on write once recording media, where recording is allowed only once. In general, the presence of defects in a recording medium is detected by recording data on the recording medium and then confirming whether or not data has been written correctly on the recording medium. However, once data is written on a write once recording medium, it is impossible to thereafter overwrite new data and manage defects on the write once recording medium.
Other methods, apparatuses, and computer readable media for managing defects on write once recording media, where written data cannot be erased or rewritten, include the methods, apparatuses, and media potentially including the use of a reproducing and/or recording medium drive, to produce a defect managed write once recording medium.
However, the defect management performed by a reproducing and/or recording medium drive can be abnormally discontinued due to an unavoidable accident, e.g., when power supplied to the reproducing and/or recording medium drive is interrupted due to a power failure. Therefore, an apparatus, method, and computer readable medium has been developed and described herein to generate a resultant defect managed recording medium regardless of such interruptions.

Method and apparatus for managing defects in recording media, a computer readable medium including computer readable code for the same, and a defect managed recording medium obtained using the same method, apparatus, and computer readable medium


A computer architecture that includes a hierarchical memory system and one or more processors. The processors execute memory access instructions whose semantics are defined in terms of the hierarchical structure of the memory system. That is, rather than attempting to maintain the illusion that the memory system is shared by all processors such that changes made by one processor are immediately visible to other processors, the memory access instructions explicitly address access to a processor-specific memory, and data transfer between the processor-specific memory and the shared memory system. Various alternative embodiments of the memory system are compatible with these instructions. These alternative embodiments do not change the semantic meaning of a computer program which uses the memory access instructions, but allow different approaches to how and when data is actually passed from one processor to another.

This invention relates to a computer architecture that includes a shared memory system.
Many current computer systems make use of hierarchical memory systems to improve memory access from one or more processors. In a common type of multiprocessor system, the processors are coupled to a hierarchical memory system made up of a shared memory system and a number of memory caches, each coupled between one of the processors and the shared memory system. The processors execute instructions, including memory access instructions such as "load" and "store," such that from the point of view of each processor, a single shared address space is directly accessible to each processor, and changes made to the value stored at a particular address by one processor are "visible" to the other processor. Various techniques, generally referred to as cache coherency protocols, are used to maintain this type of shared behavior. For instance, if one processor updates a value for a particular address in its cache, caches associated with other processors that also have copies of that address are actively notified by the shared memory system and the notified caches remove or invalidate that address in their storage, thereby preventing the other processors from using out-of-date values. The shared memory system keeps a directory that identifies which caches have copies of each address and uses this directory to notify the appropriate caches of an update. In another approach, the caches share a common communication channel (e.g., a memory bus) over which they communicate with the shared memory system. When one cache updates the shared memory system, the other caches "snoop" on the common channel to determine whether they should invalidate any of their cached values.
In order to guarantee a desired ordering of updates to the shared memory system and thereby permit synchronization of programs executing on different processors, many processors use instructions, generally known as "fence" instructions, to delay execution of certain memory access instructions until other previous memory access instructions have completed. The PowerPC "Sync" instruction and the Sun SPARC "Membar" instruction are examples of fence instructions in current processors. These fences are very "course grain" in that they require all previous memory access instructions (or a class of all loads or all stores) to complete before a subsequent memory instruction is issued.
Many processor instruction sets also include a "prefetch" instruction that is used to reduce the latency of Load instructions that would have required a memory transfer between the shared memory system and a cache. The prefetch instruction initiates a transfer of data from the shared memory system to the processor's cache but the transfer does not have to complete before the instruction itself completes. A subsequent Load instruction then accesses the prefetched data, unless the data has been invalidated in the interim by another processor or the data have not yet been provided to the cache.

Computer architecture for shared memory access


Described is a lithium-ion battery spacer having a spacer board with two operably coupled apertures disposed therethrough. The operably coupled apertures can be tapered to further facilitate smooth passage of a cathode or anode tab therethrough and secure such tab thereby minimizing tilting or shorting of the tab. Accordingly, the spacer leads to safer and more efficient production of the lithium-ion battery.

Batteries with high energy and efficiency driven by chemical reactions have been employed in mobile communications, camcorders, cameras, portable instruments and other related devices. In addition, studies have focused on using such batteries to power electric vehicles and conduct space exploration, with batteries becoming the preferred alternative energy source. As such, the demand for high performing secondary batteries is on the rise.
Generally, the assembly process for a square-shaped lithium-ion battery involves: (1) providing a battery core; (2) coupling cathode and anode tabs from the battery core through apertures on a spacer board with the tabs being separated by a ledge; (3) securing the spacer board to the top of the battery core; (4) inserting the battery core within a battery shell; and (5) sealing the battery core and the battery shell with a battery cover. The spacer board separates the cover from the core ensuring that the two does not make physical contact thus minimizing potential shorts and improving battery safety.
Reference is now made to FIGS. 1-3 illustrating a prior-art battery 10 having a core 24 housed within a shell 28 and capped with a cover 26. The battery 10 further includes a spacer 12 having a board 14 with a generally rectangular aperture 16 disposed therethrough. The spacer board 14 can be configured to receive and secure a cathode or anode tab 22a through the aperture 16 while the other tab 22b can be coupled to another part of the spacer board 14. A ledge 18 may be employed to prevent shorting of the tabs 22a, 22b. However, if the aperture 16 is too wide, the tab 22a may tilt or move about while situated within the aperture 16. In some instances, the tabs 22a, 22b may come into contact with each other thus causing electrical shorts and safety concerns. Conversely, if the aperture 16 is too narrow, it may be difficult and time consuming to insert the tab 22a therethrough thus lowering productivity and efficiency of the manufacturing process.
As such, there exists a need for a spacer that facilitates the assembly process for a lithium-ion battery.


Object of the present invention is to provide a process for producing an amide compound with high efficiency by subjecting an oxime compound to Beckmann rearrangement in a liquid phase under mild reaction conditions. Namely, the invention relates to a process for producing an amide compound such as xcex5-caprolactam by subjecting an oxime compound such as cyclohexanone oxime to Beckmann rearrangement in a liquid phase, characterized in that the reaction is carried out in the presence of (1) a non-fluorine-containing sulfonic anhydride and an N,N-disubstituted amide compound or (2) at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof, an N,N-disubstituted amide compound, and a carboxylic anhydride.

The present invention relates to a process for producing an amide compound. More specifically, it relates to a process for producing an amide compound effectively by carrying out Beckmann rearrangement of an oxime in a liquid phase in the presence of a catalyst.
Generally, as an industrial process for producing an amide compound, a process of converting an oxime compound into an amide compound through Beckmann rearrangement. For example, xcex5-caprolactam is produced through Beckmann rearrangement of cyclohexanone oxime. For such Beckmann rearrangement, currently a liquid-phase reaction has been adopted using a strong acid such as concentrated sulfuric acid or fuming sulfuric acid as the catalyst. However, in this known method, there are problems that, for separating the lactam compound formed, the sulfuric acid should be usually neutralized with ammonia to result in the formation of ammonium sulfate in an amount twice the amount of the above lactam compound as a by-product, and the reaction apparatus is corroded since a large amount of the strong acid is used. Therefore, the process is not necessarily economical and thus, it is expected to develop an effective catalyst for the rearrangement.
Therefore, Beckmann rearrangement in liquid phase has been variously investigated without using the sulfuric acid catalyst. For example, the following process are proposed for Beckmann rearrangement of cyclohexanone oxime in liquid phase using homogeneous catalysts: a process using an ion pair obtainable by reacting N,N-dimethylformamide with chlorosulfonic acid (a Vilsmeier complex), as the catalyst [M. A. Kira and Y. M. Shaker, Egypt. J. Chem., 16, 551 (1973)]; a process using a catalyst composed of an N,N-dialkylformamide and an alkylating agent obtainable from an epoxy compound and a strong acid (boron trifluoride-etherate or the like) [Y. Izumi, Chemistry Letters, pp. 2171 (1990)]; a process of rearranging cyclohexanone oxime with a phosphoric acid or a condensed phosphoric acid compound in a heptane solvent (Japanese Patent Laid-Open No. 149665/1987); a process using a catalyst composed of phosphorus pentoxide and a fluorine-containing strong acid or its derivative and a compound such as N,N-dialkylformamide (Japanese Patent Laid-Open No. 105654/1993; corresponding to U.S. Pat. No. 5,254,684); and the like.
However, the processes for producing xcex5-caprolactam by subjecting cyclohexanone oxime to Beckmann rearrangement in a liquid phase using these catalyst systems are not always satisfactory as industrial processes. Specifically, in the above Beckmann rearrangement of cyclohexanone oxime using a Vilsmeier complex as the catalyst, the lactam produced and the catalyst form a 1:1 complex, so that it is necessary to use the catalyst in an amount equimolar to the starting oxime. For this reason, the process cannot be said to be an economical industrial process. The process using a catalyst composed of an N,N-dialkylformamide and an alkylating agent obtained from an epoxy compound and a strong acid shows a novel method for the rearrangement, which is different from the conventional equimolar reaction using sulfuric acid as the catalyst. However, it is industrially not always satisfactory in view of operability because toxic compounds such as dimethyl sulfate and epichlorohydrin are sometimes used for producing the alkylating agent which is one of the rearrangement catalyst components. Further, in the process using phosphoric acid or a condensed phosphoric acid as the catalyst disclosed in Japanese Patent Laid-Open No. 149665/1987, the phosphoric acid catalyst is required in an amount as large as about 2 mol per 1 mol of the starting oxime, so that the process results in a large load on the catalyst-neutralizing step with ammonia after the reaction. Therefore, the process cannot be said to be economical industrial process.
In the process using a catalyst composed of phosphorus pentoxide and a fluorine-containing strong acid (e.g., a fluorine-containing sulfonic anhydride) or its derivative and a compound such as N,N-dialkylformamide disclosed in the above Japanese Patent Laid-Open No. 105654/1993 (U.S. Pat. No. 5,254,684), the catalyst shows a high catalytic activity but the specification describes that the catalytic activity is deactivated by the action of a trace amount of water, so that it is necessary to remove moisture strictly from the starting oxime, a reaction solvent, a reaction apparatus, and the like. In particular, the phosphorus pentoxide compound, a component of the catalyst, is known as a strong dehydrating agent by those skilled in the art, and thus, owing to the extremely high hygroscopicity, the handling is accompanied by a considerable care and troublesomeness. In addition, trifluoromethanesulfonic anhydride (a fluorine-containing strong acid compound) for use as a constituting component of the catalyst is effective as a highly active component of the catalyst, but is expensive and causes a problem of corrosion of the apparatus.
As described above, the catalyst systems heretofore proposed are not always satisfactory for the industrial production in view of catalyst efficiency, handling, and economical efficiency.
Object of the present invention is to provide a process for producing an amide compound with high efficiency through Beckmann rearrangement of an oxime compound in a liquid phase in the presence of an acid catalyst, by rearranging the oxime catalytically under a mild reaction conditions and using a small amount of catalyst, which is free from the above problems.
As a result of the extensive studies of catalysts for Beckmann rearrangement of an oxime compound into an amide compound, the present inventors have found that an amide compound can be obtained in a yield as high as in the case of the conventional process by carrying out the rearrangement using a catalyst comprising an aromatic sulfonic anhydride or non-fluorine-containing aliphatic sulfonic anhydride and an N,N-disubstituted amide compound without using an expensive fluorine-containing strong acid compound which is heretofore considered to be essential as a constituting component of the catalyst, and have attained the present invention.
Also, they have found that an amide compound can be obtained with higher efficiency by carrying out the rearrangement in the presence of at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof, an N,N-disubstituted amide compound, and a carboxylic anhydride, and have attained the invention.
Namely, the first gist of the invention lies in a process for producing an amide compound by subjecting an oxime compound to Beckmann rearrangement in a liquid phase, characterized in that the reaction is carried out in the presence of a non-fluorine-containing sulfonic anhydride and an N,N-disubstituted amide compound.
The second gist of the invention lies in a process for producing an amide compound by subjecting an oxime compound to Beckmann rearrangement in a liquid phase, characterized in that the rearrangement is carried out in the presence of at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof, an N,N-disubstituted amide compound, and an carboxylic anhydride.
As the preferred embodiments of the first gist of the invention, in the above process for producing an amide compound, it may be mentioned that the sulfonic anhydride is a non-fluorine-containing sulfonic anhydride, for example, a non-fluorine-containing benzenesulfonic anhydride or a non-fluorine-containing alkylsulfonic anhydride which may have a substituent, particularly p-toluenesulfonic anhydride or methanesulfonic anhydride, and the N,N-disubstituted amide compound is N,N-dimethylformamide, as well as the oxime compound is cyclohexanone oxime and the amide compound is xcex5-caprolactam.
As the preferred embodiments of the second gist of the invention, in the above process for producing an amide compound, it may be mentioned that the sulfonic acids are aromatic sulfonic acids or aliphatic sulfonic acids, for example, benzenesulfonic acids or alkylsulfonic acids which may have a substituent, at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof is p-toluenesulfonic anhydride, methanesulfonic anhydride, p-toluenesulfonic acid, or methanesulfonic acid, the N,N-disubstituted amide compound is N,N-dimethylformamide, and the carboxylic anhydride is acetic anhydride, as well as the oxime compound is cyclohexanone oxime and the amide compound is xcex5-caprolactam.
The following will explain the detail of the present invention.
(Oxime Compound)
Any known oxime compound can be used, without limitation, as the starting oxime compounds to be used in Beckmann rearrangement in the present invention. Specific examples of the oxime compound include oxime compounds having 2 to 20 carbon atoms, preferably 3 to 13 carbon atoms, such as cyclohexanone oxime, cyclopentanone oxime, cyclododecanone oxime, acetone oxime, 2-butanone oxime, acetophenone oxime, benzophenone oxime, 4xe2x80x2-hydroxyacetophenone oxime and the like. Among them, cyclic oxime compounds having 4 to 20 carbon atoms, preferably 5 to 13 carbon atoms, such as cyclohexanone oxime, cyclopentanone oxime, cyclododecanone oxime, and the like are preferably used.
(Catalyst for the First Gist)
The catalyst for the rearrangement to be used in the invention of first gist of the present invention contains a non-fluorine-containing sulfonic anhydride and an N,N-disubstituted amide compound as constituting components. In present, it is not clear what form of an active species of catalyst is formed from these catalyst-constituting components. However, since the reaction proceeds by the action of the starting oxime compound, the starting oxime compound can be considered to be one component of the catalyst-constituting components.
Non-fluorine-containing Sulfonic Anhydride
The non-fluorine-containing sulfonic anhydride to be used as a constituting component of the present catalyst is not particularly limited and includes a non-fluorine-containing aromatic sulfonic anhydride or a non-fluorine-containing linear or cyclic aliphatic sulfonic anhydride. A non-fluorine-containing aromatic sulfonic anhydride having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms which may have one or more substituents on the aromatic ring or a non-fluorine-containing aliphatic sulfonic anhydride having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms which may have a substituent can be used (wherein the substituent represents an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an acyl group having 2 to 4 carbon atoms, and a halogen atom such as C1 or Br). The valence number of the non-fluorine-containing sulfonic anhydride is not particularly limited but has preferably a valence number of 1.
Specific examples include benzenesulfonic anhydride, p-toluenesulfonic anhydride, m-xylene-4-sulfonic anhydride, p-dodecylbenzenesulfonic anhydride, 2,4-dimethylbenzenesulfonic anhydride, 2,5-dimethylbenzenesulfonic anhydride, 4-chlorobenzenesulfonic anhydride, xcex1-naphthylsulfonic anhydride, xcex2-naphthylsulfonic anhydride, biphenylsulfonic anhydride, methanesulfonic anhydride, ethanesulfonic anhydride, propanesulfonic anhydride, 1-hexanesulfonic anhydride, 1-octanesulfonic anhydride, and the like. Among them, preferred is a non-fluorine-containing benzenesulfonic anhydride or alkylsulfonic anhydride, particularly preferred is p-toluenesulfonic anhydride or methanesulfonic anhydride.
The rearrangement proceeds when a fluorine-containing aromatic sulfonic anhydride is used instead of a non-fluorine-containing sulfonic anhydride which is a constituting component of the catalyst for the rearrangement to be used in the invention. However, as mentioned above, since the fluorine-containing strong acid compound is extremely expensive, it is essential to establish a technology of recovering and re-using the fluorine-containing strong acid compound for establishing an economical industrial production process.
The amount of the non-fluorine-containing sulfonic anhydride to be used in the invention is not particularly limited but, in general, the compound is used in an amount ranging from about 0.2 to 20 mol %, preferably 1.0 to 15 mol %, more preferably 2.0 to 12 mol % based on the starting oxime. When the amount is smaller than the range, a sufficient catalytic activity cannot be attained, while use of too large amount requires much load for treating the catalyst after the rearrangement. Thus, both are not preferred.
N,N-Disubstituted Amide Compound
The N,N-disubstituted amide compound to be used in the catalyst system of the invention is generally a carbamide, especially formamide having the same or different alkyl groups having 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms on the nitrogen atom. Examples of the substituents on the nitrogen atom include an alkyl group, an alkoxy group, an aryl group and the like. Among them, an alkyl group is preferred and an amide compound having no cyclic structure containing the nitrogen atom is preferred. Specific examples of the compound include N,N-dimethylformamide, N,N-diethylformamide, N,N-di-i-propylformamide, N,N-dibutylformamide, N,N-dipentylformamide, N,N-dioctylformamide, N-methyl-N-stearylformamide, dimethylacetamide, diethylacetamide, and the like. Among them, a compound in which two alkyl groups are the same is preferred and particularly preferred is N,N-dimethylformamide.
The amount of the above N,N-disubstituted amide compound to be used is not particularly limited, and the amount varies with the amount range of the starting oxime compound used and the amount range of the catalyst to be combined, such as sulfonic anhydride and therefore, is not determined uniformly. However, the amide compound is generally used in an amount of 1 to 1000 times by weight, preferably 2 to 100 times, more preferably 4 to 50 times, by weight as much as the oxime compound. Also, the amide compound is used in a molar ratio of generally 10 to 2000, preferably 25 to 1000, more preferably 50 to 500 relative to the non-fluorine-containing sulfonic anhydride.
The N,N-disubstituted amide compound to be used in the invention is a constituting component of the catalyst but also acts as a solvent at the same time. Therefore, in the case that suitable other solvent is used for smooth proceeding of the rearrangement, the amide compound can be used in combination with the solvent.
(Catalyst for the Second Gist)
The catalyst for the rearrangement used in the invention of first gist of the present invention contains a non-fluorine-containing sulfonic anhydride and an N,N-disubstituted amide compound as constituting components. In the invention of the second gist of the present invention, however, an amide compound can be produced in higher yields under mild conditions by using a catalyst containing at least one compound selected from sulfonic acids and anhydrides thereof, an N,N-disubstituted amide compound, and a carboxylic anhydride as constituting components.
As the sulfonic acid or its anhydride, at least one compound selected from aromatic sulfonic acids, linear or cyclic aliphatic sulfonic acid and anhydrides thereof may be mentioned without particular limitation. An aromatic sulfonic acid having 6 to 20 carbon atoms which may have one or more substituents on the aromatic ring (e.g., benzenesulfonic acid), an aliphatic sulfonic anhydride having 1 to 20 carbon atoms which may have a substituent (e.g., an alkylsulfonic acid) and anhydrides thereof can be used (wherein the substituent represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an acyl group having 2 to 4 carbon atoms, and a halogen atom such as Cl, Br, F etc.). The valence number of the compound is not particularly limited but it has preferably a valence number of 1.
Specific examples include benzenesulfonic acid, p-toluenesulfonic acid, p-toluenesulfonic acid monohydrate, p-dodecylbenzenesulfonic acid, 2,4-dimethylbenzenesulfonic acid, 2,5-dimethylbenzenesulfonic acid, 4-chlorobenzenesulfonic acid, 4-fluorobenzenesulfonic acid, xcex1-naphthylsulfonic acid, xcex2-naphthylsulfonic acid, biphenylsulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, 1-hexanesulfonic acid, 1-octanesulfonic acid, and anhydrides thereof, and the like. Among them, preferred are methanesulfonic acid, trifluoromethanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, p-dodecylbenzenesulfonic acid, and anhydrides thereof, and particularly preferred are methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid and anhydrides thereof. The catalyst of the second gist of the present invention uses a carboxylic anhydride, which remarkably increases the catalyst activity and reduces the cost of the catalyst. In such as case, a fluorine-containing sulfonic acid compound may be used as the sulfonic acid or the anhydride thereof but it is more preferable to use a non-fluorine-containing sulfonic acid compound to further reduce the cost of the catalyst.
The amount of the at least one compound selected from sulfonic acids and anhydrides thereof in the invention is not particularly limited but, in general, the compound is used in the range of about 0.2 to 20 mol %, preferably 1.0 to 15 mol %, more preferably 2.0 to 12 mol % to the starting oxime. When the amount is smaller than the range, a sufficient catalytic activity cannot be attained, while use of too large amount requires much load for treating the catalyst after the rearrangement. Thus, both are not preferred.
N,N-Disubstituted Amide Compound
As the N,N-disubstituted amide compound to be used in the catalyst system of the second gist of the present invention, a similar kind and amount to those of the N,N-disubstituted amide compound in the catalyst system of the first gist mentioned above can be used. The amount to be used is in the range of a molar ratio of generally 10 to 2000, preferably 25 to 1000, more preferably 50 to 500 relative to the sulfonic acid and its anhydride.
Carboxylic Anhydride
The carboxylic anhydride to be used in the catalyst system of the invention is not particularly limited and an aliphatic carboxylic anhydride having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms which may have a substituent or an aromatic carboxylic anhydride having 6 to 12 carbon atoms which may have a substituent can be used (wherein the substituent represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an acyl group having 2 to 4 carbon atoms, a halogen atom such as Cl, Br, F etc.). The valence number of the carboxylic anhydride is not particularly limited but it has preferably a valence number of 1. Specific examples include acetic anhydride, propionic anhydride, n-butyric anhydride, n-valeric anhydride, n-caproic anhydride, n-heptanoic-anhydride, 2-ethylbexanoic anhydride, benzoic anhydride, phthalic anhydride, maleic anhydride, succinic anhydride, and the like. Among them, preferred is an alkylcarboxylic anhydride having 1 to 4 carbon atoms, particularly preferred are acetic anhydride and propionic anhydride which are compounds having low boiling points, and most preferred is acetic anhydride.
The amount of the carboxylic anhydride to be used in the invention is not particularly limited, but in general, the compound is generally used in the range of molar equivalent of about 0.5 to 200, preferably 1.0 to 100, more preferably 2.0 to 50 to the at least one compound selected from the group consisting of the above aromatic sulfonic acids, aliphatic sulfonic acids and anhydride thereof. When the amount is smaller than the range, a sufficient catalytic activity cannot be attained, while use of too-large amount requires much load for separating the catalyst after the rearrangement.
(Solvent)
Examples of the solvent to be used in the rearrangement of the invention other than the N,N-disubstituted amide compound include aliphatic hydrocarbon compounds such as n-hexane, n-heptane, n-octane, and n-dodecane; aromatic hydrocarbon compounds such as benzene, toluene, xylene, mesitylene, monochlorobenzene, and methoxybenzene; nitrile compounds such as acetonitrile, propanenitrile, capronitrile, adiponitrile, benzonitrile, and tolunitrile; ester compounds such as dimethyl phthalate, dibutyl phthalate, dimethyl malonate, and dimethyl succinate; and the like. Aromatic hydrocarbon compounds are preferred in view of enhancing the solubility of the starting oxime and the catalyst components. They may be used alone or as a mixture.
In the case of using a solvent other than the N,N-disubstituted amide compound, the solvent may be mixed in an amount of 0.001 to 20 times by volume, preferably 0.1 to 10 times by volume, more preferably 0.5 to 1 times by volume as much as the N,N-disubstituted amide compound. The mixing within such a range can reduce the load at the separation by distillation of the N,N-disubstituted amide compound after the reaction.
(Reaction Conditions)
The conditions for carrying out the process of the present invention are not particularly limited but the reaction is carried out at a temperature ranging generally from 0 to 200xc2x0 C., preferably from 40 to 150xc2x0 C., more preferably from 60 to 130xc2x0 C. The reaction pressure is also not particularly limited and the reaction is carried out under a pressure ranging from normal pressure to enhanced pressure. The reaction time or residence time is generally from 10 seconds to 10 hours, preferably 1 minute to 7 hours.
In the invention, the rearrangement proceeds even when each catalyst component and the starting oxime compound are mixed in any order. In the case of the catalyst system of the first gist, for example, it is preferred that the non-fluorine-containing sulfonic anhydride and the N,N-disubstituted amide compound are mixed and heated at a predetermined temperature, and then a raw material solution in which the oxime is dissolved is fed gradually thereto to start the reaction. In the case of the second catalyst system, for example, it is preferred that at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof and the carboxylic anhydride are added to the N,N-disubstituted amide compound, and the resulting mixture as it is or after addition of a small amount of a starting oxime is heated at a predetermined temperature, followed by gradual feeding of a raw material solution in which the oxime is dissolved thereto to start the reaction.
In that case, the starting oxime compound can be provided as a solution dissolved in a part of the N,N-disubstituted amide compound. It is not preferred to start the reaction at such a state that a high concentration of the oxime compound is present in the above catalyst component solution by feeding the starting oxime compound all at once because early deactivation of the catalyst and increase of by-products may be invited.
(Reaction Mode)
The reaction mode for carrying out the reaction of the invention is not particularly restricted and both of a batch reaction and a continuous flow reaction can be carried out, but a continuous flow reaction mode is preferably used in the industrial production. The type of the reactor is not particularly limited and a general reactor such as a reactor composed of one tank or two or more continuous tanks, a tubular reactor, or the like may be used. Since an acid catalyst is used in the invention, the material to be used for the reactor is preferably a corrosion resistant material. Examples thereof include stainless steel, Hastelloy, Monel, Inconel, titanium, a titanium alloy, zirconium, a zirconium alloy, nickel, a nickel alloy, tantalum, or a fluorine resin, a variety of glass materials whose inside are coated, and the like.
It is preferred that the starting oxime compound, the catalyst components, and the reaction solvent to be used in the reaction are provided into the reaction after prior thorough removal of moisture in view of attaining a high catalytic activity and a high selectivity to the amide compound.
With regard to the reaction mode of the first gist of the invention, the following will explain specifically by reference to an example of a continuous flow reaction.
An N,N-disubstituted amide compound solution in which a non-fluorine-containing sulfonic anhydride is dissolved and an N,N-disubstituted amide compound solution in which a starting oxime compound is dissolved are continuously fed to an reactor, if necessary, together with an inert solvent, and they are allowed to react during a desired residence time. At the same time, a reaction mixture containing an amide compound formed, unreacted oxime compound, and the catalyst components is continuously taken out. In the case of the second gist of the invention, a continuous flow reaction can be carried out in a similar manner to the reaction mode of the above first gist of the invention with the exception that an N,N-disubstituted amide compound in which at least one compound selected from the group consisting of sulfonic acids and anhydrides thereof and a carboxylic anhydride are dissolved is provided.
(Treatment After the Reaction)
The reaction mixture taken out contains low-boiling by-products, the solvent, a carboxylic acid (in the case that a carboxylic anhydride is used), the N,N-disubstituted amide compound, the objective amide compound, unreacted oxime, and remaining catalyst components. The reaction mixture is then introduced into a distillation column to remove successively the low-boiling by-products, the solvent such as toluene, the carboxylic acid (in the case that a carboxylic anhydride is used), and the N,N-disubstituted amide compound which is one of the catalyst components by distillation, whereby a mixture containing the amide compound of the objective product, the unreacted oxime compound, and the catalyst components is obtained. The recovered inert solvent and the N,N-disubstituted amide of a catalyst-constituting component can be recycled into the reactor, but in that case, unnecessary by-products are separately removed by separation with a separating means such as distillation.
The mixture containing the amide compound of the objective product, the unreacted oxime compound, and the remaining catalyst components is, for example, neutralized by adding an aqueous solution of an alkali compound such as NH3 or NaOH to deactivate the catalyst and then a solvent such as toluene is added thereto as a negative solvent to precipitate the deactivated catalyst as solids, whereby it is effected to separate the amide compound of the objective product and the oxime compound from the catalyst. Then, the mixture of the solvent, the objective amide compound, and the oxime compound is separated into the inert solvent and the objective amide compound and the oxime compound by means of any of various separating operations such as separation by distillation, separation by extraction, separation by crystallization, or the like. The recovered inert solvent can be recycled into the reactor, but in that case, unnecessary by-products are separately removed by separation with a separating means such as distillation. A more highly pure product of the objective amide compound can be obtained by purification through further introducing the compound into a distillation column.
The catalyst salt deactivated and separated by adding an alkali compound such as NH3 or NaOH, for example, an aromatic sulfonate salt can be easily converted into the corresponding sulfonic acid with, for example, an strong acid such as sulfuric acid, hydrochloric acid, or nitric acid, or a solid acid, an acid-form ion exchange-resin, or the like. The regenerated sulfonic acid compound can be converted into the corresponding sulfonic anhydride through easy dehydration under mild conditions, for example, by contacting with a dehydrating agent such as fuming sulfuric acid, diphosphorus pentoxide, or condensed phosphoric acid. The regenerated sulfonic acid or sulfonic anhydride can be recycled to the reactor, optionally together with an inert solvent.


According to this invention, an oxide film is formed on a semiconductor substrate, a metallic boron film or a film containing at least one selected from the group consisting of boron, phosphorus, and arsenic is deposited on the surface of the resultant structure. At least one selected from the group consisting of boron, phosphorus, and arsenic is doped from the metallic boron film or the film containing at least one selected from the group consisting of boron, phosphorus, and arsenic to the oxide film by diffusion without diffusing into the semiconductor substrate. Thus, a semiconductor device having good radiation resistance can be obtained.

1. Field of the Invention
The present invention relates to a method of manufacturing a radiation resistant semiconductor device used in, e.g., a space satellite, or a nuclear power plant.
2. Description of the Related Art
It is known that when an ionizing radiation such as an x-ray, a Y-ray, or a high-energy charged particle is radiated onto a semiconductor device, a large amount of electron-hole pairs are created in an oxide film. It is well known that a drift velocity of electrons in an oxide film is higher than that of holes. For this reason, the electrons of the electron-hole pairs generated in an oxide film disappear faster than the holes, and the many holes are left, and some portion of these holes are trapped in the oxide film. Therefore a p-type substrate under the oxide film can be inverted into an n-type one due to these trapped holes. As a consequence, when the positive charges (holes) are trapped in a field oxide film, a leakage current between circuit elements is increased. When the positive charges are trapped in a gate oxide film, a threshold voltage of the transistor is changed. Moreover, in a small-geometry LDD transistor, when many positive charges are trapped in the oxide film formed on side walls of a gate electrode, a strong accumulation of electrons otherwise in a low-electron concentration n.sup.- -type region occurs. Therefore, the transistor cannot be operated as an LDD transistor.
As conventional techniques for overcoming the above problem, a guard-band structure is employed to the field oxide film, the field oxide film is formed at a low temperature, or the field oxide film is made of two layers. In addition, it is known that a decrease in thickness and a treatment at a low temperature are effective to hardening of an oxide film.
However, in a semiconductor device having the guard-band structure, since the circuit elements must be arranged in consideration of radiation resistance in a mask design, the design becomes difficult. When the field oxide film is formed at a low temperature, a long time is required for growing the oxide film. Therefore, this method is not practical in the manufacture. In addition, when the oxide film is formed to have two layers, an interface between the two layers disadvantageously disappears by annealing after formation of the oxide film.
As for the oxide film on the side wall of the gate electrode of the LDD transistor, a technique for enhancing radiation resistance has never been developed.

Method of manufacturing radiation resistant semiconductor device


The present invention addresses the problem of providing a temperature sensing body capable of sensing both a temperature increase and a temperature decrease, and having an anti-tampering function. In order to solve said problem, this temperature sensing body is characterized by including: a first ink in which a temperature Ta1 for initiating color disappearance when the temperature rises and a temperature Td1 for initiating color development when the temperature falls are different; and a second ink in which a temperature Ta2 for initiating color disappearance when the temperature rises and a temperature Td2 for initiating color development when the temperature falls are different, wherein the temperature Ta1 for initiating color disappearance, the temperature Td1 for initiating color development, the temperature Ta2 for initiating color disappearance, and the temperature Td2 for initiating color development have the relationship, Td1<Td2<Ta1<Ta2.

Fresh foods, frozen foods, and medicinal products stored at low temperatures such as vaccines and biomedicinal products need a cold chain for keeping at a low temperature without interruption during the process of production, transportation and consumption. Actually, in order to continually measure and record the temperatures during distribution, generally, a data logger capable of continuously recording times and temperatures is installed in a transport container in many cases. Therefore, in a case where a product is damaged, the locus of responsibility can be clarified. Furthermore, in a case where the quality of an individual product is to be ensured, a method utilizing a temperature indicator is exemplified. A temperature indicator does not have a recording accuracy as high as that of a data logger, but can be attached to an individual product, and the surface is dyed in a case where the temperature is greater than or lower than a temperature that has been set in advance. Therefore, it is possible to know a change in temperature environment.
However, a managed temperature range for vaccines and biomedicinal products is 2 to 8° C., and detection of both temperature increase (8° C. or more) and temperature decrease (2° C. or less) is required. In a case where temperature management is required in a certain temperature range, a data logger is the most useful. On the other hand, in order to manage an individual product as mentioned above, a data logger is not useful for individual management due to its price and size.
Furthermore, as a temperature indicator capable of detecting both temperature increase and temperature decrease, PTL 1 discloses a temperature-indicating agent utilizing a leuco dye.


Designated files are automatically scanned for instances of a first string pattern. When a text file containing an instance of the first string pattern is found, each instance of the first string pattern in the text file is automatically replaced with a second string pattern and an annotation of the nature of the changes made to the file automatically created. This process is automatically repeated on the remainder of the designated files until complete. Inputting an empty string as the second string pattern effects deletion of instances of the first string pattern in a file.

1. Field of the Invention
The present invention relates generally to editing of computerized files, and more particularly to editing of computerized text files.
2. Description of Related Art
Web sites are conventionally constructed of a plurality of individual web pages. Generally, each web page is constructed from a computerized file or files, such as graphic files and text files, that can be read by a computer system resulting in a display of data on a display screen. The computerized text files, also referred to herein as simply "files", can be written in different languages such as HyperText Markup Language (HTML), Java, and Practical Extraction and Reporting Language (PERL), as well as other coding languages suitable for implementation of a web site.
The maintenance of the text files that support the web pages of the web site is largely performed by web designers and technical writers. When changes need to be made to a web site, the individual text files affected by the changes first need to be located and then edited to effect the changes. In some instances, locating the affected text files may require a search of each text file to determine if it is affected. In larger web sites, which can be constructed of hundreds and thousands of text files, even a simple change, such as an organizational name change, can require a large amount of time to search for and edit each affected text file.
Typically, the editing process is largely a manual process. Basic editing functions are provided by some utilities and software products, but editing is performed on one file at a time. For example, the UNIX operating system provides, "grep" and "sed" commands and a VI text editor that permit string pattern replacement in an individual file. These commands are manually intensive as each file that includes the string pattern must first be located, for example, using a UNIX command "find". Then the file opened and each instance of the string pattern replaced, and then the file saved. Other operating systems typically provide commands and text editors that perform similar functions. Not only is the editing process time intensive, it is also unacceptably vulnerable to errors, such as missed edits or incorrectly entered changes by the user.
To control access and track changes made to the text files supporting the web site, many web designers and technical writers utilize a version control system. Generally, version control systems maintain an archive copy of a file, commonly termed a source file, and a history of changes made to the source file. In some version control systems, to modify a source file, the file must be checked-out from the version control system by a user. This typically results in the source file being locked to prevent more than one user at a time from modifying the source file. Checking-in the file to version control system registers the changes made to the source file and removes locks on the source file. Thus, while editing text files, a user can have to wait to obtain access to a file in order to make changes. Then after editing one file and checking-in the file so that the changes made to the file are registered in the version control system, a user would then have to manually search and edit (if applicable) the next file, repeating the process for all the text files supporting the web page that may be affected by the changes. This can be a time consuming process dependent on the availability of files and number of files.
Thus, it would be desirable to have a method that permits a user, such as a web designer or technical writer, to more quickly and efficiently edit text files, such as for a web site. Further, it would be desirable that the method permit multiple files to be scanned for a particular string pattern and automatically edited to replace a particular string pattern with a substitute string pattern, or to delete the particular string pattern. Also, it would be desirable that the method automatically annotate the changes made to the text file.