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Hey there....We're Leaving the Ashram Tomorrow Night.
Allahabad Travel Blog› entry 11 of 16 › view all entries
March 25, 2007 and it's been a truly lovely day (Indian Ashram Style of a Lovely Day, which is different from what I would have called a lovely day back home). Sundays, the schedule here is a bit different. Swami Satyam holds a service (class) which attracts more of the public. It's at least two hours of class/meditation/guided devotion etc. and I found it both challenging, rewarding, inspiring and just really good. Afterward he made note that he will meet with both Scott and myself (the meeting I've been waiting for and Scott has been wanting to talk to him too now for a couple of days) so, I'm sure that will happen soon. After the service, the kitchen serves a meal to everyone. I decided to eat Indian-style again figuring that it may be the last time while I'm here. Sitting on the ground (with lots of accompanying flies), barefoot (much of our time here is barefoot), eating off of leaf plates (disposable/biodegradeable and one of my favorite things here) and eating with your hands (definitely something to get used to because we're not talking about fries and a sandwich here, you are to mix your beans with your rice using your hands like a utensil and then scoop into your mouth, anyway, there are different techniques for different foods. And the weather is lovely today and we won't have an 11am meditation because it's too close to the first one which by the way started at 7 am instead of our usual 6am which was another reason to be happy, especially since I stayed up later than usual last night, so, in terms of sleep hours it's a wash.
I will see if I can get the tailor to sew my luggage today and get some laundry done and then a few other tasks like getting my photo cd from one of the matas and I want to take some more photos before I leave and I have people I want to be sure to say good-bye to and get contact information and I want to get some CD's (recordings of Swami Satyam's sessions) too. He records virtually every instruction that he gives. Many of them are in Hindi and English. I'd like just the English versions. I STILL have difficulty understanding him (and others) much of the time when they are speaking English. This morning I asked for more salad and I just didn't put the emphasis where they're used to and so it took awhile for Chotu to figure out what I was saying. Salad here is any raw vegetable. It could be a cut up carrot and that's, salad.
I'd like to say that I'm so even-minded that regardless of what my body was going through that I could be and was happy and loving it and though that's what I've practiced I'm not 100% there yet, so another reason why I'm having a good day so far is because my body (mostly my digestive tract) isn't going nuts with changes) so it's a nice break from that. That said, I still am aware of many physical sensations as a result of the meditations and I want to be sure to welcome it as I believe it all to be very regenerative.
Uh oh! I just remembered that I put water on the stove downstairs to boil….for drinking water and for a cup of tea….
Okay, about an hour later….I've had some tea, I ate a few of Santosh's grapes and he's in the kitchen cooking and wants me to try all his Brazilian dishes…he's one of the few who have begun to really cook quite a bit. I will try just a spoonful of his cooking which is a bit risky considering I'm going through a rare period of semi-okayness in the digestive area. I sat downstairs and chatted with Scott and Bob over our tea and we watched Santosh cook. Scott wants to use the internet so we'll walk over to another area soon to see if we can get on, then we'll find Guruji to give him our phone number so he can call us when he's ready for us. Right now Scott is shaving…something he's done a couple of times since we've been here. Later we'll both do laundry it sounds like. Man, what a lovely feeling day it is today.
Navin's email said that we'll go to an Indian restaurant when we arrive in
I'm feeling more and more up to traveling over to
I largish, black bug was crawling on my bare shoulder last night while I was sleeping and I woke up to it…..I grabbed it, squished it with a napkin type thing which I have by the bed for just that reason and then I rolled over and went back to sleep without skipping a beat. Well, that's an example of adjusting to a new environment don't you think? Though, Indians may have just slept through it or shoed it away. I did it Western-style with an Indian attitude : )
2pm now and man am I having a great day…ahhhhhhhhhhhhhhhhhhhhhhhhhhhhhh : ))
I'm going to blog Scott's final draft of his Kriya Yoga testimonial.
March 26, 2007
Last night had it's ups and downs and ended on an upside. Then, a lovely morning. Difficult meditation but good. Then all sorts of little miracles throughout the day. And today again, I'm just marveling at the many physical changes of my body. Don't know what will happen with it all over time and away from here, but like everyday here, I'm taking and observing and learning and experiencing for the moment and the day, so for now I'm content with the experiences and unlike me, I've really worked at not analyzing everything, figuring out how and why and wondering about what next to do etc.
Anandamata just told us that her birthday was yesterday…..a nice friend who is in our room right now reading an email from her daughter using Bob's computer who is in here too. I don't know details but Scott just started experiencing the vomiting/diarrhea drill, but he seems in good enough spirits so, no worries mom and dad.


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Smile Empty Soul have announced their new album 'Rarities,' a compilation album built out of previously unreleased tracks written over the course of the last 14 years. The album will be release on March 10, 2017.
I'm happy to be releasing all these songs we've recorded over the years that never made our regular albums. its gonna be cool to see them get out there to our fans and maybe play a few of them at our live shows
– Sean Danielsen
Smile Empty Soul vocalist and guitarist Sean Danielsen also independently released his debut solo album 'Product of Isolation' on January 13, 2017. (Amazon MP3/iTunes)
This album was my first venture into having a home studio and engineering and producing completely on my own. it was an amazing experience to make and i hope people can relate to it. i definitely poured myself into the songs, and i think that shows
– Sean Danielsen
1. One at a Time
2. Something New
3. Alone
4. Goodbye
5. This is War
6. Wasted Town
7. Whats Going Through My Head Right Now
8. For You
9. Who I Am
10. Finding Myself
11. Precious Things (Tori Amos Cover)
12. Aneurysm (Nirvana Cover)
13. Possession (Sarah McLachlan Cover)

subset: commoncrawl


text:
Mike from Liberty, Mo writes,
I want to use this product to prevent borers on my larage shade trees. How many ounces should I use per gallon...
Mixing Hi-Yield 38-Plus Insect Control - 38% Permethrin at 1.6 fl uid ozs. (3 1/4 Tablespoons) per 1 gallon of spray solution to make a 0.5% spray emulsion.
To prevent infestation of Ornamental Trees and Woody Shrubs, spray the bark to the point of saturation, but do not let runoff occur. Repeat treatment every 21 days during early Spring until Mid-Summer
Answer last updated on: 03/30/2015
1 of 1 people found this answer helpful. Was it helpful to you? Yes No


text:
Java and Project Delivery. E&CE 250 Winter 2002. http://ece.uwaterloo.ca/~rrolon/java/tutorial.ppt http://ece.uwaterloo.ca/~rrolon/java/tutorial.pdf. We are using the Java 2 Version 1.3 SDK java -version It provides the following tools:. Java on Polaris. javac java javadoc jar jdb
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Winter 2002
We are using the Java 2 Version 1.3 SDKjava -version
It provides the following tools:Java on Polaris
The compiler for the Java programming language
The launcher for Java applications
API document generation
Creation and management of Java Archive files
The Java Debugger
The launcher for Java applets
1. Log onto Polaris
2. Open the MS-DOS prompt from Windows
3. Create a ece250 directory in n:\
n:\ mkdir ece250
4. Edit n:\privexec.bat and add the lines:
set PATH=%PATH%;q:\eng\ece\jdk1.3\bin
set CLASSPATH = N:\ece250
5. Run the batch file n:\privexec.bat again
public class StringOperations {
public static void main (String[] args) {
String str = "If there were dreams to sell, What would you buy?";
System.out.println ("The string is: " + str);
System.out.println ("The length is: " + str.length());
System.out.println ("Substring 14-20: " + str.substring(14,20));
System.out.println ("Uppercase is: " + str.toUpperCase());
Note: For a Java program to compile properly, the name of the file and class defined must be the same. Remember: file name = class name.
If it works, you'll see:The string is: If there were dreams to sell, What would you buy?
The length is: 49
Substring 14-20: dreams
Uppercase is: IF THERE WERE DREAMS TO SELL, WHAT WOULD YOU BUY?
Exception in thread "main"
This will happen if you forgot to set the classpath to include your working directory.
* The StringOperations class represents manipulation of strings
* @author Ricardo Rolon
* @version 1.0, Sep 2001
public class StringOperations {
* Creates a String object.
public static void main (String[] args) {
String str = "If there were dreams to sell, What would you buy?";
System.out.println ("The string is: " + str);
System.out.println ("The length is: " + str.length());
System.out.println ("Substring 14-20: "+ str.substring(14,20));
System.out.println ("Uppercase is: " + str.toUpperCase());
Javadoc -author -version StringOperations.java
Example: jar cvmf myManifestFile myJarFile *.class *.html *.java
Where c option indicates that a jar file must be created,
v means to be Verbose
m include my own Manifest file
fput the .jar file in a separate File whose name is provided
The Java Virtual Machine needs to know which .class file in the .jar file contains the main( ) method. To do that, create a text file with just one line:
Main-Class: <MainJavaClass>
For instance, in Project 1, if Rational.class is the class that contains main(), then MyManifestFile should contain the following line:
Main-Class: Rational
Don't forget to end the Main-Class line with a carriage return, otherwise jar will not recognize it.
1. Compile the program: javac -g StringOperations.java
2. Start the debugger: jdb StrigOperations
3. Set breakpoints:
stop in StringOperations.main
stop at StringOperations:15
4. Run program: run StringOperations
5. Extract debugging info with commands:
list, locals, print, step, cont
6. Recompile the program: javac StringOperations.java
Keep this in mind:
We have to be able to compile it and run it on the Java 2 SDK 1.3 platform


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CRC for Developing Northern Australia
The White Paper on Developing Northern Australia was released on 18 June 2015 and included $75 million over 10 years to establish a Cooperative Research Centre (CRC) for Developing Northern Australia. The CRC is a core element of the Australian Government's agenda for developing the north.
The CRC will assist businesses, governments and researchers to work together to identify opportunities for business and growth in the north. The CRC will be industry led, located in the north, and have an initial focus on areas where the north has particular strengths, including agriculture, food and tropical health. It will bring together industry, research organisations, all northern jurisdictions and international partners in a collaborative industry-led R&D venture.
The CRC will build on existing research, expertise and networks to quickly identify areas where collaborative research can deliver real-world outcomes and commercial opportunities that will benefit industries in northern Australia. The CRC will also establish strong links with the Australian Government's flagship Industry Growth Centres initiative.
Mr John Wharton AM was appointed as Interim Chair of the CRC in November 2015 to consult with stakeholders and develop a proposal for consideration by Government to establish the CRC. Mr Wharton undertook extensive consultations with industry, research and government from December 2015 to 31 March 2016 and provided his proposal to Government on 5 August 2016.
The Australian Government announced in April 2016 that the City of Townsville will host the administrative headquarters of the CRC for Developing Northern Australia.
On 20 February 2017, the Australian Government announced the following members of the board that will lead the establishment of the CRC:
- Ms Sheriden Morris, Chair
- Mr Don McDonald AM OBE
- Cr John Wharton AM
- Cr Peter Long
- Ms Tracey Hayes
- Mr John Bearnes
- Ms Melissa George
This board will work closely with stakeholders to establish the CRC over the coming months.
The Government also announced the opening of an early project funding round in advance of the establishment of the CRC for Developing Northern Australia.
The CRC for Developing Northern Australia Project Funding round will provide grants of up to $3 million over terms of up to three years for collaborative research projects which address industry problems in tropical health and medicine, including models of care; and tropical and northern agriculture including animal and plant improvement and sustainability. Grants will be awarded through an open, competitive project funding round administered by AusIndustry in the Department of Industry, Innovation and Science.
Applications for the round opened on 20 February 2017 and closed on 22 May 2017.
On 17 October 2017, the Hon Barnaby Joyce MP, Deputy Prime Minister and Minister for Resources and Northern Australia, and the Hon Craig Laundy MP, Assistant Minister for Industry, Innovation and Science, announced the outcomes of the project funding round. View the list of projects offered funding under the CRC Program.
Further information
For further information on the Northern Australia Project Funding Round, contact AusIndustry on 13 28 46 or Email us.
The CRC for Developing Northern Australia is located at 214-216 Charters Towers Road, Hermit Park, Queensland, 4812. Further information on the CRC and its activities is available on the CRC website.


text:
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An excerpt from www.HouseOfNames.com archives copyright © 2000 - 2017
Anglo-Saxon surname lappan came from the baptismal nameLapin. The surname lappan referred to the son of Lapin which belongs to the category of patronymic surnames. In Old English, patronyms were formed by adding a variety of suffixes to personal names, which changed over time and from place to place. For example, after the Norman Conquest, sunu and sune, which meant son, were the most common patronymic suffixes. In the 12th and 13th centuries, the most common patronymic names included the word filius, which meant son. By the 14th century, the suffix son had replaced these earlier versions. Surnames that were formed with filius or son were more common in the north of England and it was here that the number of individuals without surnames was greatest at this time.
lappan Early Origins
Kent, where they held a family seat from the Middle Ages.
lappan Spelling Variations
lappan Spelling Variations
Sound was what guided spelling in the essentially pre-literate Middle Ages, so one person's name was often recorded under several variations during a single lifetime. Also, before the advent of the printing press and the first dictionaries, the English language was not standardized. Therefore, spelling variations were common, even among the names of the most literate people. Known variations of the lappan family name include Lappin, Lapping, Lappine, Lapinus, Lapyn, Lappyng, Lapine, Lappen and many more.
lappan Early History
lappan Early History
This web page shows only a small excerpt of our lappan research. Another 218 words (16 lines of text) covering the years 1320, 1481, and 1749 are included under the topic Early lappan History in all our PDF Extended History products and printed products wherever possible.
lappan Early Notables (pre 1700)
lappan Early Notables (pre 1700)
More information is included under the topic Early lappan Notables in all our PDF Extended History products and printed products wherever possible.
lappan In Ireland
lappan In Ireland
Some of the lappan family moved to Ireland, but this topic is not covered in this excerpt. Another 182 words (13 lines of text) about their life in Ireland is included in all our PDF Extended History products and printed products wherever possible.
The Great Migration
The Great Migration
For political, religious, and economic reasons, thousands of English families boarded ships for Ireland, the Canadas, the America colonies, and many of smaller tropical colonies in the hope of finding better lives abroad. Although the passage on the cramped, dank ships caused many to arrive in the New World diseased and starving, those families that survived the trip often went on to make valuable contributions to those new societies to which they arrived. Early immigrants bearing the lappan surname or a spelling variation of the name include:
lappan Settlers in United States in the 19th Century
lappan Settlers in United States in the 20th Century
lappan Family Crest Products
lappan Family Crest Products
See Also
See Also
Other References
The lappan Family Crest was acquired from the Houseofnames.com archives. The lappan Family Crest was drawn according to heraldic standards based on published blazons. We generally include the oldest published family crest once associated with each surname.
This page was last modified on 17 August 2016 at 09:27.
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text:
|Publication number
|Publication type
|Application number
|Publication date
|Mar 23, 1993
|Filing date
|Jul 1, 1992
|Priority date
|Jul 1, 1992
|Fee status
|Also published as
|Publication number
|George B. Litchford, Burton L. Hulland
|Original Assignee
|Litchstreet Co.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (1), Referenced by (16), Classifications (12), Legal Events (6)
|External Links: USPTO, USPTO Assignment, Espacenet
This invention relates generally to passive air traffic control and collision warning systems which utilize interrogation signals transmitted from a ground SSR station and associated transponder reply messages transmitted by vehicles, such as aircraft, that are elicited by the SSR, for determining the ranges, azimuth angles, altitude and identity of one vehicle relative to another or to the ground station and, more particularly, is concerned with improvements to systems of this type, specifically the collision avoidance system described in applicants, U.S. Pat. No. 4,486,755.
The system shown in U.S. Pat. No. 4,486,755, the disclosure of which is hereby incorporated herein by reference, receives standardized interrogation signals, having the waveforms shown in FIG. 1, transmitted from a ground station at a frequency of 1030 MHz on a narrow rotating main beam and in the side lobes of the main beam. The standardized interrogation signal consists of three pulses each 0.8 μsec. wide: a P1 pulse; a P2 pulse spaced 2.0 μsec. from the P1 pulse; and a P3 pulse spaced from P1 by either 8.0 μsec or 21.0 μsec. The P1 and P3 pulses are transmitted by the main beam and also, unintentionally, by the main beam side lobes which, unless suppressed, may be sufficiently strong to interrogate nearby transponders, creating false replies. Referring to FIG. 2, the rotating directional antenna that has been employed over the past several years, many of which likely will still be in service for many years to come, produces a scanning beam 10 which is about 2.5° to 3.0° wide at its 3dB point and slightly wider at its suppression control point.
In most SSRs, a second, static antenna omnidirectionally broadcasts a side lobe suppression control pattern 12 containing P2-only pulses or P1-P2 pulse pairs, wherein the P2 pulse is synchronized with the P1 pulse in the main beam, at a significantly higher level than the main beam side lobes, the purpose of which is to prevent transponder replies to other than main beam interrogation pulses when such main beam pulses exceed the P2 pulse suppression signal level by a fixed amount. On some SSR control patterns only P2 pulses are transmitted, which combine with the P1 pulses of stronger main beam side lobes to create a P1-P2 suppression pair. More specifically, the radiated amplitude of P2 at the transponder is (1) equal to or greater than the signal amplitude of P1 from the greatest side lobe transmission of the antenna radiating P1 (i.e., the rotating main beam 10) and (2) at a level lower than 9dB below the radiated amplitude of P1 within the desired arc of interrogation. When main beam P1 pulse levels exceed P2 pulse levels, P3 is no longer suppressed and P1-P3 pulse pairs interrogate transponders that are in the main beam.
A P1-P3 pulse pair with a separation of 8.0 μsec. between P1 and P3 transmitted on the main beam interrogates the identity (Mode A) of a transponder-equipped aircraft, and a separation of 21.0 μsec. between P1 and P3 interrogates that aircraft's altitude (Mode C). A series of about twenty such P1-P3 pulse pairs, one-half of which typically are Mode A interrogations and the other half Mode C interrogations, is received at a transponder, within a beam's width, during each 360 degree scan of the rotating beam. During the period that the rotating beam is pointing at the transponder, that is, the time the beam takes to scan approximately 4°, known as the "beam-dwell" time, the transponder replies in accordance with the "un-suppressed" P1-P3 spacings of the interrogation message. Interlaced Mode A and Mode C interrogation messages, such as ACACAC, or AACAAC, are separated by intervals typically of about 2500 μsec. but in the range between a minimum of about 2,000 μsec. to a maximum of approximately 5,000 μsec. The broad SLS pattern, being significantly stronger at all azimuths outside of the main beam skirt (approximately 14-16 dB down from the main beam peak), prevents interrogation pulse pairs from being received by a transponder unless they are in the sector defined by the 3°-4° width of the main beam.
Summarizing, a P1-P3 pulse pair transmitted on the SSR main beam will interrogate an airborne transponder, causing it to transmit mode A and mode C messages, only if the amplitude of the P1-P3 pulses received at the transponder exceeds the amplitude of any received associated P2 pulses. Each qualifying transponder within the 360° scanning coverage of the SSR main beam transmits in response a reply message on a 1090 MHz radio frequency carrier back to the SSR, with a known delay, so that the reply message is propagated along the path of the main beam and thus its signal strength is increased by beam gain, and received by a 1090 MHz receiver at the SSR. Each such 1090 MHz transponder transmission, known as a "reply message" and depicted in FIG. 3, includes a pair of framing pulses F1 and F2 separated by 20.3 μsec. which define the start and stop, respectively, of the message, between which thirteen information pulses (twelve of which are currently used) are spaced in increments of 1.45 μsec. from the first framing pulse, each of which is 0.45 μsec. wide and may or may not be present depending upon the content of the message transmitted in reply to the 1030 MHz interrogation signal. The format of the message contained between framing pulses F1 and F2 is similar for any one of 4,096 identity codes transmitted. The absence or presence of each of twelve information pulses establishes which code is transmitted on 1090 MHz in response to the reception of an interrogating P1-P3 pulse pair spaced by 8.0 μsec.
Similarly, the format of the message contained between the framing pulses is the same for any one of the altitude codes, which do not use D1 pulses, each of which represents the altitude of the aircraft to within ±50 feet in 100-foot increments up to a maximum in excess of 125,000 feet. Thus, the structure of the reply message allows for the possibility of 4,096 different code groups, each representing one or more pieces of information such as identity or altitude of the responding aircraft. As previously mentioned, 1030 MHz P1 and P3 interrogation pulses separated by 8.0 μsec. when decoded elicit a reply code group transmitted on 1090 MHz representing identity. Similarly, a P1-P3 spacing of 21.0 μsec. elicits a reply code representing the altitude of a given aircraft. As assigned by ATC or other authorities such as the military, the identity code is set in by the pilot with a cockpit "digit switch", while the altitude code is automatically established by a barometric altimeter and an associated encoder. The identity code designations consist of four digits, each of which lies between 0 and 7, inclusive, and is determined by the sum of the pulse subscripts given in FIG. 3. The identity code of the aircraft may be 1543, for example, which is represented by the presence of A1 ; (B1 B4); C4; and (D1 D2) pulses. The transponder automatically continuously transmits this identity code in response to every received Mode A interrogation regardless of which radar is interrogating, the beam width of the interrogating radar, or whether it is a civil, military or European radar.
In a similar manner, in response to interrogation P1-P3 pulses spaced by 21.0 μsec., the transponder automatically looks at an automatic altitude encoder coupled to the aircraft's own barometric altimeter, which automatically changes the code with changes in altitude according to a pattern prescribed by the U.S. NATIONAL STANDARD FOR THE IFF MARK X (SIF) AIR TRAFFIC CONTROL SYSTEM (Oct. 10, 1968), and the reply message transmitted by the transponder is changed accordingly. Although the altitude information is presented in the same pulse format as the identity information, the ground system readily discriminates between Mode A and Mode C replies to its interrogation, because the relatively long interval between PRPs, and thus between interrogation messages, is such that only during a specific period of, say 3,000 μsec., representing a round trip of about 250 nautical miles (3000/12 μsec. per NM), following an interrogation message wherein the P3 pulse is spaced from P1 by 8.0 μsec., all aircraft that are within the beam and within 250 NM respond with identity codes. Since the ranges of most SSR radars are limited to about 200 miles line-of-sight, all targets reply within typically 2500 to 3000 μsec. During the following PRP, during which, say a Mode C interrogation is transmitted by the SSR, all aircraft out to a similar predetermined range that are intercepted by the main scanning beam will reply only with altitude codes. In this way there is no confusion between identity and altitude replies even though both use identical signal formats, because each pulse has a different significance. These identity and altitude codes are interpreted by an airborne collision warning system in the same way as does the ground station so as to provide collision warning data on all nearby transponders.
In the passive threat warning and collision avoidance system described in the '755 patent, an Own station receives interrogations from at least one and usually multiple SSR's within operating range, not only when the main SSR beam is pointing at it but also when Own station is illuminated by lower level side lobes of one or more main beams, and capitalizes on time of arrival (TOA) data from multiple SSRs to create a small cocoon of airspace that represents the approximate range and near exact altitude of any nearby transponder-equipped aircraft that may be a threat to Own's aircraft. Use of such transponders is mandated in some 240,000 aircraft in the United States alone and about 350,000 worldwide.
During a brief "listen-in" period of about 200 μsec. initiated by Own's reception of a P1-P3 decode, Own station receives replies transmitted by transponders at Other stations in the general vicinity of Own station in response to each interrogation from an SSR. The received replies are decoded and using the P3 time of the associated interrogation message received by the transponder's 1030 MHz receiver, produce time of arrival (TOA) data for all surrounding aircraft and SSR stations within the sensitivity range of the Own station's 1030 MHz and 1090 MHz receivers. Operation of the '755 system depends on the amplitude of the side lobes of the rotating main beam being sufficiently high that a P1-P3 pulse pair would be received via the main beam side lobes so long as that receiver was within a given operating range of an SSR. Thus, the '755 system provides such TOA measurements not only during, but also before and after passage of the main beam, so long as P1-P3 pulse pairs can be received; the rotating main beam may be pointing in a direction other than at Own station and interrogating other transponders. Consequently, it is essential to the operation of the '755 system that it receive P1-P3 pulse pairs, and the associated 1090 MHz responses, both before and after passage of the SSR main beam through Own's station, throughout an angular sector of about ±30° straddling the main beam's axis. The inability to receive P1-P3 pulse pairs in the deep nulls between the many such side lobes limited the effectiveness of the system.
The last decade has witnessed an evolutionary change in the design of ground SSR antennas, in particular the antenna system employed in SSR systems of the type here under discussion. Several hundred U.S.-based SSR's are now or are in the process of being equipped with an improved antenna system which is electrically phased so as to create a narrow, main scanning beam on which P1-P3 interrogation pulses are transmitted and reply messages are received, and which has very low side lobes. The new antennas usually do not include the static stand-alone antenna used in the earlier system for omnidirectionally broadcasting a P1-P2 side lobe suppression pattern, but, instead, employ antenna structure and radiating elements integral and rotatable with the rotating main beam-forming antenna structure for generating an SLS control pattern. As shown in FIG. 4, the SLS control pattern of this new system, containing either P1-P2 pulse pairs or only stand-alone P2 pulses, is generally "egg-shaped" in the horizontal plane, or may have a narrow null along the main beam's axis. The maximum signal of the SLS pattern, and therefore its maximum range of reception, is aligned with the axis of the main beam 16 and rotates with it; thus, the maximum signal level and therefore the range of the rotating SLS pattern traces an imaginary circle 18 as it rotates with the main beam. However, the signal strength is maximum only within a sector approximately ±40° wide which straddles the rotating main beam. The signal level of the SLS control pattern in the direction of the main beam typically is about 14 dB to 16 dB down from the peak amplitude of the main beam and about 20 dB above the average level of the main beam side lobes. The level of the control pattern above the side lobe level varies with the angular displacement from the main beam, as much as 30 dB at an angle of 180° from the main beam, while averaging approximately 20 dB above the main beam side lobes during a rotation period. The new SLS pattern exhibits high signal levels, without deep nulls, at all azimuths, within the ±40° angular sector straddling the main beam, outside of which there is some diminution in level but still greatly exceeding the level of the main beams side lobes.
Unfortunately, however, this recent reduction in level of the main beam's side lobes turns out to be a disadvantage to the '755 system, the operation of which depends on reception of P1-P3 pulse pairs, not only those contained in the main beam but also those transmitted in and between adjacent side lobes. Consequently, the major reduction in side lobe level provided by the improved SSR antenna significantly reduces the operational range of the '755 system and, indirectly, the accuracy of its collision warnings, by reducing the probability of receiving multiple SSR's at most locations. As the population of improved antenna systems becomes larger, the useful collision warning range of '755 systems could be reduced.
Adding to the challenge is the fact that of the approximately 3,000 SSR's currently in service throughout the world, some already are using the improved antenna system, others are in the process of being updated, and others may continue using the "old" system, without change, for many more years. It is projected that there will be a "mix" of old and new antenna systems for approximately ten to twenty years before the "old" antennas are totally phased out.
Thus, there is a current and compelling need for a passive threat warning and collision avoidance system that is adaptable to the radiation characteristics of both the "old" and the "new" SSR antenna systems. The system should also be operable in geographical areas where only the P2 pulse is transmitted in the SLS control pattern, as is the case of SSR's in England and some other European countries. Some U.S. stations such as ASR-9 SSRs may also transmit only P2 pulses on the SLS control pattern.
Accordingly, the primary object of the present invention is to provide an "adaptive" collision avoidance system embodying the principles of the '755 system and capable of operation with any of the three types of ground radar transmission systems described above.
Another object of the invention is to extend the useful range of such system from an SSR thereby to increase the probability that SLS signals from two or more SSRs interrogating nearby targets will be received by the collision avoidance system and thereby significantly reduce false alarms and provide more precise measurement of pseudo-range.
Additionally, the system must be passive (that is, it should not itself transmit for the purpose of detecting a potentially colliding airplane), thus avoiding interference on either the 1030 MHz channel or the 1090 MHz channel of the standardized SSR system.
The system should also be relatively simple and inexpensive to manufacture so as to be economically feasible for owners of light aircraft such as those used in general aviation.
In accordance with the present invention, which will be described in association with the collision avoidance system shown in U.S. Pat. No. 4,486,755, but the principles of which are also applicable to other PSSR systems such as that disclosed in U.S. Pat. No. 4,115,771. In the event P1-P3 pulse pairs are not available, the system is adapted to use either P1-P2 pulse pairs or "stand-alone" P2 pulses, for timing the "listen-in" period of an Own station. More specifically, in the event of unavailability of P1-P3 pulse pairs, of which P3 is normally used for initiation of time of arrival (TOA) measurements, the system automatically selects, as a second choice, P1-P2 pulse pairs because of their pulse width and unique separation by exactly 2.0 μsec. and selects, as a third choice, stand-alone P2 pulses, for timing the "listen-in" period. The amplitude of the P2 pulse contained in the SLS radiation pattern of both the "old" and the improved SSR antenna system is greater than the level of the main beam side lobes over an angular range of at least about ±40° from the direction of the main beam axis, which insures its reception, before and after passage of the main beam through a transponder, at ranges much greater than the range at which side lobes of the main beam and nulls between them can be reliably received. For example, by quadrupling the reception range in the ±40° sector, which is readily possible, by using P2 signal strength versus the much weaker side lobe P3 signal strength and deep nulls between side lobes the useful air-to-air collision protection area surrounding an SSR is increased by a factor of sixteen. This increase would also apply to any adjacent SSR's within Own's operating range, thereby providing large overlapping protection areas.
That P2 time (derived from either the P2 pulse of a P1-P2 pair or a "stand-alone" P2 ) can be used for synchronizing TOA measurements is based on the different spacings between P2 and P3 pulses in Mode A and the P2-P3 spacing of Mode C interrogation messages, and the fact that Mode A and Mode C reply messages elicited by an interrogating main beam mimic most of the interrogation messages and other characteristics of the beam. From Own's examination of the 1090 MHz "mimic" patterns, it is possible to use P2 time to measure TOA values of reply messages. More particularly, since the spacing between P2 and P3 pulses is exactly 6.0 μsec. (8 minus 2) for Mode A (identity) and 19.0 μsec. (21 minus 2) for Mode C (altitude), if P2 pulse time, instead of P3 pulse time, is used to synchronize the start of the "listen-in" period during which the TOA of a Mode A or a Mode C reply message is measured, the TOA can be corrected, if the interrogation mode is known, to a "synthetic" P3 time. However, the time difference between Mode A reply relative to P2 time and a Mode C reply relative to P2 time will always be exactly 13.0 μsec. (19 minus 6).
This 13.0 μsec. difference in TOA measurements is critical to the system's ability to identify and separate Mode A and Mode C replies. The typical 1090 MHz "beam burst" of about twenty reply messages received at the Own station transponder during each scan of a scanning SSR beam past Other contains an approximately equal mix of Mode A and Mode C reply messages. Importantly, all Mode A replies will have shorter TOAs, relative to P2, than similar TOAs of Mode C replies. Because the "mimic" of the beam received on 1090 MHz at Own station will contain the interrogating radar's PRP, and the spacing and interlace pattern of the Mode A and Mode C interrogation messages, by initiating time of arrival (TOA) measurements with a P2 pulse, two "families" of TOA's, both referenced to P2 time, are created, one family of essentially equal TOAs for Mode A and another family of essentially equal TOAs for Mode C. By virtue of the 13 μsec. time differential between the two families of TOAs, and the fact that the reply messages are contained in the same "burst", they can be readily identified and separated.
Other objects, features and advantages of the invention will become apparent, and its construction and operation better understood, from the following detailed description when read in conjunction with the accompanying drawings.
FIG. 1, to which reference has already been made, are waveforms depicting standardized Mode A and Mode C interrogation signals;
FIG. 2, also referred to previously, is a simplified diagram of a ground SSR interrogation system and depicts the radiation patterns of "old" antenna systems;
FIG. 3, previously referred to, is a diagram showing the standardized code characteristics of reply messages;
FIG. 4, to which reference has previously been made, shows the integrated radiation pattern of the "new" antenna systems coming into use in SSR systems;
FIG. 5 is a rectangular plot of the interrogation beam pattern and control beam pattern typical of the new antenna systems;
FIGS. 6A and 6B placed together side by side as shown in FIG. 7 is a block diagram, partly functional, of a collision avoidance system embodying the invention; and
FIG. 8 is a geometric diagram used in explaining the operation of the system of FIGS. 6A-6B with two favorably located SSRs.
Briefly referring again to FIG. 4, newer ground SSR stations differ from the one depicted in FIG. 2 in the significant respect that they have a phased array antenna which creates the interrogation radiation pattern shown in plan view in FIG. 4 comprising a narrow clockwise rotating main beam 16 and a much wider "egg-shaped" side lobe suppression control pattern 14 which is aligned with, and rotates along with, the narrow scanning beam. The side lobes of the main beam of the new antennas are very low in signal power, which greatly reduces the useful range of systems such as that described in the '755 patent that depends for its operation on direct reception of P1-P3 pulses contained in the multi-beam side lobes. All SSR ground stations, whether equipped with the "old" or the newer antenna system, transmit on the main scanning beam at a frequency of 1030 MHz, the internationally standardized interrogation signals shown in FIG. 1, consisting of three 0.80 μsec. pulses; equal-amplitude P1 and P3 pulses separated by a specified interval and a lower amplitude P2 control pulse separated from the P1 pulse by 2.0 μsec. The ATCRBS (SSR) system relies on pulse amplitude comparison between pulses P1 and P2 as received by the transponder to prevent response to side lobe interrogation, and the Standards therefore specify that the radiated amplitude of P2 at the antenna of the transponder shall be (1) equal to or greater than the radiated amplitude of P1 from the side When main beam P1 pulse levels exceed P2 pulse levels, P3 pulses are no longer suppressed and the transponder replies by transmitting on 1090 MHz over the desired arc of main beam interrogation. The signal strengths at different azimuths outside the main beam's angular sector are such that the P2 or P1-P2 combination is always greater than the P1-P3 combination and thereby "suppress" any transponder, preventing it from receiving P3 pulses contained in the side lobes.
Side lobe suppression control pulses P2, synchronously locked to the timing of the main beam P1-P3 pulses, are radiated at the same frequency using the same time-shared transmitter, i.e., 1030 MHz, on a control pattern. In much of the United States the control pattern is as depicted in FIG. 5, a predominant P2 pulse, a P1 pulse 3 dB down from the level of P2, both of which dominate a P3 pulse, with the P1-P2 pair dominating the P1-P3 side lobe pulse pairs. In Great Britain and in some European countries the control signal of FIG. 5 consists of only the P2 pulse which predominates any received P1 or P3 pulse outside the main beam and, accordingly, will suppress the transponder when a P1 from a strong side lobe combines with the control pattern's single P2.
The relative amplitude levels of the main beam 10 and its side lobes and the SLS control pattern of the "old" antenna system shown in FIG. 2 are quantitatively depicted in FIG. 5, wherein all levels are indicated in terms of dB down from the peak level (0 dB) of the main beam 10 used for transmitting interrogation signals on 1030 MHz. The peak signal level of the control beam typically is 16 to 18 dB below the peak level of the main beam. At any azimuth the relative amplitude of the pulses changes with the rotating antenna's instantaneous direction such that the level of pulse P2 is greater than that of P1 in all directions except in the direction of the main beam. Similarly, as shown in FIG. 4, the relative amplitude of the pulses change with antenna direction such that the signal strength of the P2 pulse is greater than that of any P1-P3 pair in all directions except for the narrow angular sector of the main beam. Thus, the "old" and the improved antenna systems both produce radiation patterns which contain P2 pulses greater in strength than P1-P3 pulses over a wide angular sector except in the main interrogate beam which essentially bisects the angular sector. Importantly, this insures long range reception of P2 pulses, both before and after passage of the main beam through a transponder's location, whether radiated by an "old" or a "new" antenna, so as to be available for TOA timing purposes in the event normally-used P3 pulses are absent.
Referring now to FIGS. 6A and 6B, a receiver 20 is designed to receive via an antenna 22 standard interrogation signals and side lobe suppression signals transmitted at the SSR frequency of 1030 MHz from a ground station. The antenna may be a highly directive antenna pointed at a distant radar in the case of a passive ground radar, or it may be omnidirectional for an airborne application; the invention will be described in an airborne environment. Because of constraints placed on the location of antennas on aircraft, it is typical to use a single antenna that both receives at 1030 MHz and transmits at 1090 MHz located on the bottom of the aircraft, especially in the case of small general aviation aircraft, although sometimes both top and bottom mountings are used with two receivers to create a diversity system. The bottom antenna mounting is preferred in a low-cost system because the ground antennas are beneath the aircraft with the consequence that a bottom mounted antenna receives a stronger signal than an antenna mounted on the top of the aircraft.
The output of receiver 20 is applied to a threshold device 24 arranged to pass to a pulse width discriminator 25 any output from receiver 20 exceeding a predetermined threshold level. The pulse width discriminator eliminates all pulses except those having a pulse width which satisfies the 0.80 μsec. width and other specifications of standard interrogation pulses. The qualifying pulses are passed to a P1-P3decoder 26 designed to provide an output on line 26A when an identity (Mode A) interrogation is received, or an output on line 26B when an altitude (Mode C) interrogation is received. These outputs are applied as information inputs to a switch 28.
The P1-P3 decoder 26 also provides an output on line A which represents the P3 pulse of each received and decoded interrogation containing P1 and P3 pulses spaced by either 8.0 μsec. or 21.0 μsec., establishing that the receiver is being interrogated by the main beam of an SSR or that the SSR is sufficiently close to Own that the signal strength of the main beam side lobes is high enough for P1-P3 pulse pairs to be received consistently. All P3 pulses provided on line A by decoding of received P1-P3 pulse pairs are passed with first priority by a priority selector device 32 for use as the synchronizing signal for measuring TOA's.
The 0.8 μsec. pulses passed by pulse width discriminator 25 are applied to a P1-P2 decode 27 which provides an output on line B when the received interrogation passed by threshold device 24 and pulse width discriminator 25 contains two 0.80 μsec. wide pulses spaced, between their leading edges, by 2.0 μsec., which establishes that the system is receiving P1-P2 pulse pairs conveyed by the SLS wide beam control pattern of an SSR within the extended operating range of such stations. The amplitude of P1 compared to P2 can differ, but a pulse pair decode can occur so long as both are above threshold within a typically 50 db dynamic range. An output on line B is assigned second priority by priority selector device 32 and is coupled to a box 82 labeled "P1-P2" for utilization in a manner to be explained later.
The interrogation pulses passed by threshold device 24 and pulse width discriminator 25 are also applied to a pulse storage device 36 which is repeatedly opened and closed by a reset line 38 at 50.0 μsec. (±25 μsec.)intervals to provide an approximately 50 μsec. "window" during which the applied signal is examined to determine whether any other pulse or pulses similar to a single P2 pulse have appeared either before or after it. Thus, absent P1-P3 pairs, P1-P2 pairs, or "stray" pulses within the 50 μsec. window, a "stand-alone" P2 pulse can be detected. The output of this "window", which will be either an 0.8 μsec. wide pulse or multiple similar pulses,, is applied in parallel to a processor which includes a unit 40 that examines the stored data and passes only one single 0.8 μsec. wide pulse, if present, and to a unit 42 which examines the same stored data and detects if there are other 0.8 μsec. wide pulses contained within the 50 μsec. "window" period. If unit 42 determines that multiple pulses are not present, a "kill data" bus incorporated therein is not activated and precludes an output from unit 42; when the "kill data" bus is not activated a single pulse detected by unit 40 is passed to one input of a unit 44 labeled "Single P2" and provides an output on line C, establishing that only a single P2 pulse exists within the 50 μsec. window. If, on the other hand, unit 42 detects additional pulses, the "kill data" from unit 40 applied to a second input of gate 44 will kill or terminate such pulses including a single P2 pulse detected by unit 40.
The just-described process is available again immediately after either the "killing" of multiple 0.80 μsec. pulses or the passing of a stand-alone P2 pulse. Since, on average, 1600 P2 pulses can occur in a single rotation of the main beam (4.0 seconds/rotation×400 (PRP)), the killing of a few stand-alone P2 pulses that may result from mutual interference of multiple SSRs is generally insignificant in low and medium densities of SSR stations and the system will operate without them. For example, if the P2 pulse is killed because of the presence of multiple pulses in the window, which is wide enough to include P1-P3 messages, and this occurs say four times during the beam rotation period of four seconds, sixteen out of 1600 stand-alone P2 pulses would be lost, but the same sixteen would not necessarily be lost during the next beam rotation. However, on such occasions the P1-P3 pairs or P1-P2 pairs would be used to create the "P 3 time" via priority selector 32. Because the beam rotations of multiple adjacent SSRs and, accordingly, their interferences, are random, and the system is flexible enough to utilize data from two or three beam rotations, of two or three SSRs, the loss of such P2 pulses on an single rotation is insignificant. In a multiple SSR environment the priority can change continuously during a period corresponding to average beam rotation times. The single P2 pulses produced by this process are coupled to a box 84 labeled "P2 Only" for utilization in a manner to be explained.
The P2 pulses derived from either box 82 or box 84 are applied as one input to a switch 110, and P3 pulses, that is, the priority #1 output of priority selector 32, are applied as a second input to the switch. Switch 110 is so designed that in the absence of P3 timing pulses from selector 32 it feeds P2 pulses via line 112 to a line 68. If, on the other hand, priority #1 P3 timing is available from priority selector 32, switch 110 instead applies the P3 pulses via line 112 to line 68 for utilization in a manner to be described.
Reviewing the operation of the SSR in the just-described context, and assuming another example of a single SSR received at Own transmitting only P2 pulses (stand-alone, absent P3 absent P1) on its SLS control pattern and a main beam rotation period of five seconds, for about 99% of the time after the main beam carrying P1-P3 pulses passes the receiver, P2 pulses will be present at the PRP of the SSR, which, for example, might be 400 pulses per second, thereby producing about 2000 "stand-alone" P2 pulses nearly all of which pass through the 50-μsec. window. For the single SSR example, during the relatively long period of about 4.8 million μsec. for each rotation of the main beam in an English or European radar, the "stand-alone" P2 pulses will be separated by about 2500 μsec., with the consequence that there will be a probability of only about 50/2500, or 2% of possible "stray" P2 pulses being present in the 50 μsec.-wide window and passed as a true P2 pulse to priority selector 32. Because P2-only pulses are somewhat less reliable than a true P1-P2 pair for synchronizing the start of "listen-in" time, they are assigned a lower priority, priority #3, by priority selector 32. Should a maximum main beam side lobe conveying P1 pulses combine with a P2 pulse, priority selector 32 determine that P1-P2 priority be used. Thus, the priority selector adapts to available signals continuously throughout the time it takes for a main beam rotation.
The interrogation code priority selector 32 is so arranged that if adequate P1-P3 data is available over a given period of time, for example a few interrogation periods, then that data is used as the timing signal for measuring TOAs, just as in the system described in U.S. Pat. No. 4,486,755. However, if the SSR beam is pointing elsewhere than toward Own station, and its side lobes are at such a low level that adequate P1-P3 data is not available at Own's location, then, if employed in the United States (with P1-P2 pairs on the control pattern), decoded P1-P2 data will usually be available over a wide angular sector surrounding and moving with the main scanning beam. The United States has a population of several hundred SSR's that radiate precisely separated (2.0 μsec) pairs of P1 and P2 pulses on the SLS control pattern. If adequate P1-P2 data should be unavailable, as, for example, in systems employed in England or other European countries (and occasionally some United States SSRs) wherein only P2 pulses are transmitted on the SLS control pattern, the lower priority single P2 pulse data is utilized.
Thus, if priority #1 data is available for a "listen-in" period of 200 μsec., priority selector 32 insures that priority #2 and priority #3 data is not used. If priority #1 data is missing, but priority #2 data is available, the latter is utilized for that "listen-in" period in preference to priority #3 data. After each "listen-in" period the priority selector 32 selects in descending order the best, most likely and most useful received data at that instant. Recalling that the 200 μsec. "listen-in" period is only 10% or less of the average SSR PRP of say, 2500 μsec., following the close of the listen-in period there remains a period of about 2300 μsec. within which other radar interrogations can be interleaved. This creates many synchronizing timing signals for TOA measurements from which the best are selected by priority selector 32, thereby maximizing the operating range of the equipment while maintaining a high degree of integrity. The selections are automatic, which maximizes the data from an SSR throughout its rotation period and avoids loss of TOA data when deep nulls between main beam side lobes are pointing at the Own aircraft. For example, the present invention should extend the useful range from an SSR to an Own's airborne collision warning system constructed in accordance with U.S. Pat. No. 4,486,755 by as much as four or five times, say, from 20 miles to as much as 80-100 miles from an SSR. This can increase useful coverage area of the herein described system relative to each SSR's location by as much as twenty-five times, thereby enhancing the desired overlap of multiple SSRs.
To repeat, when P1-P3 pulse pairs are not available, P1-P2 pulse pairs, if available, are preferred over P2 -only pulses. However, if P1-P3 pairs and P1-P2 pairs are both absent, P-2 only pulses can, as will be explained presently, be used to initiate a 200 μsec. "listen-in" period for TOAs. In addition to being "adaptive" to the "old" and "new" antenna systems, the just-described decoding/priority selection process is "adaptive" in the sense that it is able continuously to examine received 1030 MHz signals to determine every few hundred microseconds (e.g. 200-300 μsec.) which of the three possible priorities are available and which of them should be utilized at that instant to time the start of the "listen-in" period. If, for example, interrogations are received from two SSRs, one of which has P1-P2 pulse pairs on the SLS control pattern and the other has only P2 control pulses, and P1-P3 pulse pairs are received from neither, the system can extract useful information from both, concurrently, as they interrogate other aircraft in the vicinity of Own. If too many SSRs are present, overload control 119 can limit SSR data to say the closest four or five SSRs.
Information contained in reply messages transmitted by Other aircraft is received at the Own station during each scan of the scanning beam of an SSR located within operating range. A 1090 MHz receiver 60, provided with an antenna 61 preferably mounted on the top of the aircraft and designed to receive standard transponder reply signals, is connected to a reply decoder 64 via a threshold device 62 designed to pass any output from receiver 60 exceeding a given threshold level, which level may be controlled by a sensitivity time control generator 66. STC generator 66 is controlled by timing pulses on line 68, which may be P3 or P2 pulses depending on the output of switch 110, to initially provide a relatively high threshold level, and then reduce the level over a period of, say 5 μsec., thereafter maintaining the lower level so as to receive weaker replies until the next P3 or P2 pulse occurs. If the equipment is embodied in a passive ground radar (PSSR), the receiver antenna 64 may be the highly directive, switched beam antenna system described in applicant Litchford's U.S. patent application Ser. No. 07/813,137, filed Dec. 23, 1991, pointed directly at the responding aircraft; if embodied in an airborne system, antenna 61 must be omnidirectional and preferably is mounted on top of the aircraft. Receiver 60 may be similar to usual transponder receivers but receiver 20 is about 20 dB more sensitive so as to be capable of operating at, typically, -91 dBm sensitivity.
A "listen-in" gate generator 70 is connected to line 68 and arranged to produce a gate signal of about 200 μsec. duration following each P3 or P2 pulse applied to line 68. The gate signal on line 70a enables the reply decoder 64, which in the absence of the gate signal is disabled. When enabled, for about 200 μsec., decoder 64 produces an output on lines 72 and 74 which represents either the identity or the altitude information contained in the current reply message, As shown in FIG. 5, each message contains an initial framing pulse F1 and a second framing pulse F2 which follows F1 by 20.3 μsec., the interval between them containing thirteen sub-intervals, of which twelve are currently used, in each of which a pulse may or may not be present, providing for possibility of 4096 different codes, each code representing one or more pieces of information. Since all messages are elicited by interrogation messages alternating between Mode A and Mode C in synchronism with P3 pulses carried by the scanning SSR beam, and both Mode A and Mode C replies utilize the same twelve sub-intervals for carrying information, it is essentially impossible to determine at Own's receiving station, using P2 timing without more data, whether a given message is a response to a Mode A or to a Mode C interrogation.
For example, a "burst" of about twenty reply messages are received by receiver 60 from an Other aircraft during each 360° scan of such Other aircraft by the scanning SSR beams. Each 1090 MHz burst, which represents 50 to 100 milliseconds of main beam dwell time depending upon the type of radar (i.e. whether it is a rapidly rotating airport radar or a slowly rotating en route radar), will produce on line 74 for application to a beam burst signal processor 76 a mix of pulse messages representing identity and altitude of each of the aircraft surrounding the Own station out to the maximum reception range of Own's 1090 MHz receiver (say, 30-40 miles). Processor 76 is enabled by a P2 pulse on line 86, the source of which will be described presently. Each data burst on line 74 is a "mimic" (or imitation) of the SSR beam (or beams) that are interrogating the airspace surrounding Own's transponder and all nearby transponders. The mimic characteristics include exact, unique SSR spacing of interrogation messages (often known as the SSR/PRP characteristics). Since all SSRs are on the same RF channel, they are effectively finger printed or identified by each having a unique PRP "signature" for interrogating; the period may be fixed or it may be staggered. The mimic also creates replicas of the Mode A and Mode C main beam interrogation patterns, such as AACAAC, ACACAC, etc., the exact beam rotation period for any SSR that is being received, the exact measured value of TOAs for Mode A replies and the exact value of TOA measured for Mode C replies when the P2 pulse is used as the start of the listen-in window in place of the P3 pulse start time used in the '755 system.
For the sake of simplicity it will be assumed that the main beam's width interrogates any transponder within its range of coverage, out to 100 miles and throughout an azimuth of 360°, and will elicit twenty replies: ten Mode A reply messages and ten Mode C reply messages. Utilizing the above-discussed observation that because of exact standardized spacing of the P1, P2 and P3 pulses, the measured TOA at Own of Other's identity (Mode A) reply messages, using P2 time, is exactly and always 13 μsec. shorter than the measured TOA of reply messages from the same Other transponder station elicited by the main beam's Mode C interrogation. When activated by a P2 pulse on line 86 (indicating a lack of P3 data), beam burst signal processor 76, using techniques extensively described in the literature, organizes the "burst" into two "histograms", a "short TOA" histogram of identity code pulses and a "long TOA" histogram of altitude code pulses. The "short" and "long" TOA histograms are applied to units 78 and 80, respectively, which correlate the F1-F2 pulses of a respective histogram relative to P2 time to determine the time of arrival (TOA). Because in this example there are ten short TOAs, by creating a histogram the processor 76 shows that the ten agree with each other closely enough (in TOA and code content) to belong to the same "family" and therefore to a single Other transponder station, and thus amenable to autocorrelation. Similarly, the ten "long TOAs" within the time duration of the beam burst are in sufficiently close agreement to belong to the same "family" and also capable of being autocorrelated. A typical 1090 MHz burst of twenty reply messages, spaced 2500 μsec. apart, has a duration of 20×2500 μsec.=50 milliseconds. The following a P2 pulse any associated 20.3 μsec. message will be received.
The "short" and "long" TOAs are individually correlated, using P2 pulses derived from either priority #2 data (box 82) or priority #3 data (box 84), and applied via line 86 to both of correlators 78 and 80. While each of the TOAs may be of any specific length, depending upon Other station's location relative to that of Own's station, because they are referenced to the P2 pulse and processor 76 is activated by the P2 pulse, the "short" and "long" TOA values in the burst of messages always must differ in length from each other by 13 μsec. Although a TOA value may be anywhere in the range from 0.1 μsec. to 200 μsec., for purposes of the discussion to follow, the "short TOA" will be arbitrarily assumed to be 46 μsec. and the "long TOA" will then, of necessity, be 59 μsec. These values are indicated in blocks 88 and 90, and a comparator 92, shown connected between these blocks establishes that the TOA value represented by block 88 is shorter by 13 μsec. than the TOA value represented by block 90. It will be understood that this 13 μsec. difference would also be satisfied if, for example, the "short" TOA were 51 μsec. and the "long" TOA were 64 μsec.
The correlated "short" and "long" TOAs which may, for example, contain a message composed of A1, B2, C4 and D1 pulses distributed between framing pulses F1 and F2, are applied to similar correlators 94 and 96, respectively, which autocorrelate the code information reply pulse-by-reply pulse. Since 4096 different Other's identity "messages" are possible, when for example two or more successive code patterns agree exactly, the probability of an erroneous output from code correlators 94 and 96 would be less than one in sixteen million (i.e., (4×103)×(4×103). Thus, the system provides the same enormous discrimination between "false" and "true" codes as that available in current SSR systems.
A "true" TOA of 40 μsec. for the "short" TOAs is obtained by subtracting (depicted by block 98) 6 μsec. (i.e., the P2-P3 spacing in Other's Mode A) from the 46 μsec. TOA represented by the autocorrelated code output of correlator 94, the same as if P1-P3 pulse pairs had been received and the TOA timed with respect to the P3 pulse instead of P2. Thus, the described correlations automatically identify the family of "short" TOAs as Mode A identification codes, which is outputted from block 100.
It is important to recognize that the TOA and the code structure really can never be separated; since the TOA is referenced to the F1-F2 framing pulses, specifically, F2 timing relative to the P3 timing (P3 actual or P2-corrected time), the information contained between F1 and F2 is always "locked-in". The code information may occasionally be garbled, but it is nevertheless locked to TOA and cannot be separated. One or two garbled messages, if present in a burst, are ignored as they do not correlate with the several others.
A "true" value of 40 μsec. for the "long" TOAs is obtained by subtracting 19 μsec. (Other's P2-P3 Mode C interrogation spacing) from the 59 μsec. TOA represented by the autocorrelated output of code correlator 96, as depicted by block 102. Because of the above-described separation of families of "long" TOAs (representing Mode C) from families of "short" TOAs (representing Mode A), the "true" TOAs depicted by blocks 100 and 104 are both 40 μsec. Other's ten Mode A replies on 1090 MHz agree exactly with Other's ten Mode C replies by the described arithmetic corrections. Consequently, twenty consistent TOA measurements are available at Own from reply messages received from Other which can be separated to provide an altitude code and an identity code of Other each associated with the same TOA, as depicted by blocks 100A and 104A. This enables the described diverse data to be combined, as represented by block 106, timed to "P2-time" but corrected after the beam burst to P3 time, just as if it were timed from two P1-P3 decodes of 8.0 μsec. and 21.0 μsec. Arbitrarily assuming a Mode A code of 1253, and a Mode C code representing an altitude of 3000 feet, by the above process it is determined from twenty replies from this aircraft (i.e., No. 1253) that the true TOA is 40 μsec. and true altitude is 3000 feet.
Thus, the just-described system produces: an output on line 105 representing altitude information contained in the current reply message; an output on line 107 representing identity information contained in the current reply message; and an output on line 109 representing the distance between Own and Other. The output on line 105 is applied to an altitude comparator 111 having as a second input data provided by an encoding altimeter 113 representing Own's altitude encoded in a similar format. Comparator 111 produces an output representing the difference between Own's and Other's altitudes when a Mode C reply occurs. The output of comparator 111 is an information input to switch circuit 28.
Briefly reviewing the priority selection process, if priority #1 P3 timing is available from priority selector 32, it is fed via line 114 to a gate generator 116, the function of which will be described presently, and via switch 110 and line 112 to line 68. In the absence of P3 pulses from selector 32, P2 pulses produced at the output of either box 82 or 84 are applied to line 86 and are also coupled via switch 110 and line 112 to line 68. Line 68 is also connected to an overload control circuit 119 arranged to control the threshold level of device 24, as in a standard ATCRBS transponder. It will be understood that any one or all three of the signals outputted by priority selector 32 can be operating concurrently depending upon the number and relative positions of multiple 1030 MHz SSRs within the surrounding environment, and the strength of the signals that are present. The extended ranges afforded by P2 timing increases the likelihood that at least two SSRs will be received, thereby creating throughout a much greater airspace higher accuracy and much fewer false alarms than the pseudo-range methods described in U.S. Pat. No. 4,486,755. The output of electronic switch 110, with P1-P3 pulse pairs always taking precedence if available, can similarly be fed to appropriate connection points of the PSSR system described in U.S. Pat. No. 4,115,771.
Returning now to the description of the collision avoidance system, a clock generator and counter 118 is arranged to be reset by each P3 pulse appearing on line 68, and to apply the current count, which may be a numerical representation of the number of microseconds elapsed since the last preceding P3 pulse was applied to counter 118. Each F2 pulse applied to a gate 120 transfers the current count to line 122. The output of gate 120 on line 122 represents the differential time of arrival TOA of a received interrogation and the corresponding received reply from a transponder at an Other station. Clock generator and counter 118 is not enabled by P2 pulses on line 68.
Whenever P3 is present on line 68, reply decoder 64 produces an output on line 72 representing either the identity or the altitude information contained in the current reply message. This output is applied to comparator 111 and to switch circuit 28; comparator 111 produces an output representing the difference between Own's and Other's altitude when a Mode C reply occurs. The output of comparator 111 in response to a Mode A reply will be spurious. In either case the output of comparator 111 is an information input to switch 28.
Multiple line 72 is connected to supply all decoded outputs timed to P3, both altitude and identity, from decoder 64 as information inputs to switch circuit 28. When a P1-P3 identity interrogation is received, line 26a is energized to actuate switch 28 to pass the identity message to switch output line 124. The output of comparator 111 at this time is discarded. When a P1-P3 altitude interrogation message is received, decoder 26 energizes line 26b, thereby activating switch circuit 28 to apply the output of comparator 111 to line 124, discarding the input from line 72.
Lines 122 and 124 are connected to a reply storage device 126, which may comprise a plurality of digital registers arranged in known manner to store associatively the TOA and identity or differential altitude information corresponding to approximately twenty successive reply messages. Preferably, the differential altitude information is stored associatively with the identity and differential time of arrival data. The information contained in each new reply message displaces the oldest such stored information, so the storage device 126 maintains a running account of identification and associated TOA and differential altitude information.
A comparator 128, when enabled by P3 via gate generator 116, compares the associated entries in storage device 126 with each other to select those nearly identical entries that appear currently in the reply storage device 126. When such a match occurs the respective entry is transferred to a selector device 130. The gate generator 116, which is similar to the "listen-in" gate generator 70, is arranged to enable the comparator 128 for a period, beginning at the end of the listen-in gate, of sufficient duration for completion of the operation of comparator 128.
The output of comparator 128 may and generally will, include several entries containing the same identity information but substantially different TOA information. The selector 130 rejects all such entries except the one containing the largest TOA, which it transfers, together with the associated identity and differential altitude information, to a selected reply storage device 132. Storage device 132 is similar to device 126, but retains its entries for a period somewhat longer than the longest radar beam rotation period to be expected, say fifteen seconds. If during that time a new entry with a larger TOA value is presented, the new larger value of TOA is substituted for the old, smaller value associated with that particular identity.
It will have been recognized that the processing performed by reply storage device 126 and comparator 128 is functionally equivalent to that accomplished in the processing of "short" and "long" TOAs 78 and 80 when beam burst signal processor 76 is enabled by the presence of a P2 pulse on line 86. As just mentioned, when P1-P3 pulse pairs are available, reply storage 126 device stores approximately twenty successive reply messages, which is the equivalent of storing a total beam burst, just as is done by the signal processor 76. In other words, when P2 is present on line 68, signal processor 76 is activated and all information contained in about twenty successive reply messages, which takes about 50 milliseconds (50,000 μsec.) to complete, is processed relative to P2 time. When P3 is present on line 68, signal processor 76 is disabled and the approximately twenty successive reply messages are, instead, stored in reply storage device 126 and compared in comparator to select those nearly identical entries that appear currently in the reply storage device 126. This being the case, whenever P2 pulses are being used for timing, the identity and TOA information present on lines 107 and 109, respectively, and the differential altitude information present on line 115, are all applied to selector 130, instead of information supplied from comparator 128 when P3 timing is available. As before, selector 130 selects information entries containing the largest TOA, which it transfers, together with the associated identity and differential amplitude information, to selected reply storage device 132.
The storage device 132 is connected to a threat detector 134 designed to transfer, following a delay of 15 seconds, any entry containing a differential altitude of less than a given valve, such as 3000 feet, and a TOA of a given valve, such as less than 36 μsec., to a display logic device 136. At the same time, detector 134 provides an output on line 138 to start an alarm timer circuit 140 which may be similar to "listen-in" gate generator 70, but designed to provide an output also lasting about 15 seconds. The output of timer 140 actuates an alarm device 142.
The display logic device 136 converts the output of detector 134 to a form suitable for display on an identity indicator 144, a differential altitude indicator 146 and a pseudo-range indicator 148. The pseudo-range indication is a display of the differential TOA in terms of distance, i.e., one-half the distance radiation travels during the time TOA. This is what is meant by pseudo-range and corresponds to the actual range to a degree that depends upon the positional relationship between Own and Other stations and the SSR. The pseudo range is never greater than the actual range. When Own and Other stations are both interrogated by a number of SSR's, the likelihood of which is enhanced by the present invention, the largest value of the pseudo-range associated with a particular Other may closely approximate the actual range of said Other.
Referring to FIG. 8, which is a plan or map-like representation showing the locations of an Own, an Other and two SSRs, line 201 represents the distance from SSR-1 to Own, line 202 represents the distance from SSR-1 to Other, and line 203 represents the range between Own and Other. The differential time of arrival T1 in this case is the difference between the sum of the travel times over paths 202 and 203 and the travel time over path 201, generally expressed in microseconds. Any particular time T1 defines an ellipse such as 204, which is a locus of Other's position, i.e., time T1 signifies only that Other is at some unspecified point on ellipse 204.
It will be seen in FIG. 8 that lines 201 and 202 are approximately parallel and thus T1 is very nearly twice the propagation delay along line 203, the true range between Own and Other. Thus (cT1)2, referred to herein as the pseudo range associated with SSR-1, is essentially equal to the true range, where c is the propagation velocity.
Line 205 represents the distance from SSR-2 to Other. In this case the differential time of arrival T2 defines ellipse 207 as a locus of Other's position. Owing to the positional relationship between Own, Other and SSR-2, the pseudo range associated with SSR-2, that is (cT2)2, cT2 is considerably less than the true range, and may be shown to be a little more than one-half the true range. Regardless of the relative position of Own and any Other station and any SSR, the pseudo range can never be greater than the true range and generally will be somewhat less. Therefore, in a multiple SSR environment the largest determined pseudo range to a particular Other is always selected by selector 130 as the value most nearly equal to the true range. Thus, the larger TOA associated with SSR-1 is selected as representative of "pseudo-range" of Other from Own.
When an Other station is much closer to the SSR than Own station the pseudo range may become a small fraction of the true range and, if the Other is within the differential altitude limits, may initiate a threat detection when in fact no threat exists. Such false threats are minimized by the action of the STC generator 66 of FIG. 6A controlling the threshold device 62 to reject relatively weak replies received within a few microseconds after reception of an interrogation.
While the principles of the invention have been described with the aid of a block diagram of a currently preferred embodiment, it will now occur to those skilled in the art that the invention can be modified in numerous ways without departing from the spirit of the invention. It is the intention, therefore, that the invention not be limited except as defined by the appended claims.
|Cited Patent
|Filing date
|Publication date
|Jun 24, 1987
|Mar 22, 1988
|Litchstreet Co.
|Position finding and collision avoidance system
|Citing Patent
|Filing date
|Publication date
|Jul 2, 1993
|Apr 12, 1994
|Secondary radar antenna operating in S mode
|Nov 17, 1994
|Apr 2, 1996
|Telefonaktiebolaget Lm Ericsson
|Method for range determination
|Jun 26, 2000
|Jul 16, 2002
|Raytheon Company
|Air traffic control system
|Jul 27, 1998
|Feb 18, 2003
|Telefonaktiebolaget Lm Ericsson (Publ)
|Identifying starting time for making time of arrival measurements
|Jul 29, 2003
|Jan 10, 2006
|Navaero Ab
|Passive airborne collision warning device and method
|Sep 13, 2005
|Feb 16, 2010
|Kabushiki Kaisha Toshiba
|Secondary surveillance radar system, and ground system for use therein
|Apr 28, 2006
|Mar 27, 2012
|Research In Motion Limited
|Method of processing notifications provided by a routine, and associated handheld electronic device
|Jul 2, 2012
|Mar 10, 2015
|Rockwell Collins, Inc.
|TCAS primary antenna on aircraft underside system and method
|Sep 28, 2012
|Feb 23, 2016
|Technische Universitat Braunschweig
|Measurement method for analysing the propagation of eletromagnetic navigation signals
|Dec 20, 2002
|May 29, 2003
|Erik Larsson
|Identifying starting time for making time of arrival measurements
|Jul 29, 2003
|Feb 3, 2005
|Navaero Ab
|Passive Airborne Collision Warning Device and Method
|Sep 13, 2005
|Aug 17, 2006
|Yoshinori Kuji
|Secondary surveillance radar system, and ground system for use therein
|Apr 28, 2006
|Jan 3, 2008
|Research In Motion Limited
|Method of processing notifications provided by a routine, and associted handheld electronic device
|Dec 20, 2007
|Jun 25, 2009
|3M Innovative Properties Company
|Radio frequency identification reader system
|Sep 28, 2012
|Aug 28, 2014
|Technische Universitat Braunschweig
|Measurement method for analysing the propagation of eletromagnetic navigation signals
|Jul 9, 2010
|Feb 2, 2011
|FCS Flight Calibration Services GmbH
|Secondary signal receiver and method for determining defined receiver times of secondary radar signals in a multilateration system
|U.S. Classification
|342/455, 342/32, 342/398
|International Classification
|Cooperative Classification
|European Classification
|Jul 1, 1992
Owner name: LITCHSTREET COMPANY, NEW YORK
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:LITCHFORD, GEORGE B.;HULLAND, BURTON L.;REEL/FRAME:006205/0454;SIGNING DATES FROM 19920626 TO 19920629
|Dec 7, 1993
|Certificate of correction
|Sep 20, 1996
|Fee payment
Year of fee payment: 4
|Sep 22, 2000
|Fee payment
Year of fee payment: 8
|Sep 23, 2004
|Fee payment
Year of fee payment: 12
|Oct 7, 2004
|Maintenance fee reminder mailed


text:
I'm really enjoying summer. Like a lot of people I'm trying to jam as much fun as I can into the few short months of good weather. The problem is that I also have to get some writing done. I've noticed that at this time of year there are a lot of interruptions, so my writing is a stop and go process. I have to keep going over what i wrote just a few hours ago to get the feel of the story and then the phone rings, or a neighbour drops by for a beer. I don't complain being interrupted for a beer.
I'm working the third novel of the Castle series and as the story gets more complex,I have to make sure the characters stay consistent with how they think and act. I also have to change them a bit as their experiences in the first two books affect them. I also have the situation of characters living in a different world than the one they were born in. That will make a character change even more. They will not be able to use accepted behaviour on their home world in their new location and will have to adjust accordingly.
I hope you are enjoying summer so far. I know I am even if I do fall behind on my work.


text:
500 craft beers is our way of professing dedication to your enjoyment. We select the local, the rare, the classic and the trendy so that your snifter, pint or koozie is always teeming with delicious liquid.
Our craft beer is delivered right to our stores so you get the freshest selection around. Visit your local ABC beer haven to browse hundreds of craft beers today!
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Grande Absente is a bitter liqueur that contains more absinthe and less sugar. Grande Absente is made from alcohol, sugar, absinthe infusions and essences, mugwort and star anise, aniseed alcohol, balm and mint.
Country: FRANCE
Varietal: CORDIALS & LIQUEURS


text:
Work-in-progress Reel
Passageira australis
Performances and presentations
Passageira em Casa is an intermedia and inter-disciplinary maritime performance inspired by the journey to define the concept of "home". The narrative is a partially fictionalized and personalized account of the Maritime history of Portugal, enacted by a dancer, a vocal performer, a live video performer, a live electronic composer, and other artists…all of or children of immigration. The text of the project is inspired by Camões, Os Lusíadas.
The text, or "lyrics", of the project are developed by the director, with poet Ian Colbert, based on Os Lusiadas; as well as Hawaiian chant, the directors ancestors diaries and memoirs, and the director's own writing. The project is inspired by various texts related to maritime journeys and Portuguese history and culture. Context specific in varying historical, cultural, lingual, architectural, and personal aspects, the project has a conceptual anchor, but will always be born new as it travels to new locations and situations as an epic Exquisite Corpse.
" 'More than a few Portuguese of my generation relate the story of as a child looking to the map of Portugal hanging in their classrooms as a face…Spain being the hair and neck…the face of Portugal in profile looking away from the known land, out to sea, past sea, to new.' (("Portuguese Modernism Unbounded: a Poetics for the 'Border Identity'" – Maria José Canelo). Somewhere in my bloodline was this experience. It leads them cross-land and two oceans to Hawaii. My mother looked back the way they came, I looked beyond where she led me. Now a bloodline becomes a circle. But is that a return? Return again implies a home base. But this speaks of many lifetimes. Can one's ancestry become a personal history? Could this feel like a return home? Could this feel like a home?"
Binaural project page
Passageira em Casa é uma perfomance intermedia e multi-disciplinar inspirada pela viagem em busca da definição de "casa". A narrativa é parcialmente ficcionada e consiste num relato pessoal sobre a história marítima de Portugal, levada à cena por uma bailarina, uma performer vocal, uma artista vídeo e um compositor sonoro e outros artistas… todos eles filhos da emigração. O texto do projecto é inspirado em Os Lusíadas, de Luís de Camões.
O texto do projecto foi desenvolvido pela directora e pelo poeta Ian Colbert, baseado n'Os Lusíadas, em cantos Havaianos, memórias e diários dos antepassados da directora, por textos da sua autoria e outros textos relacionados com viagens marítimas e história e cultura de Portugal. O projecto é adaptado a vários contextos históricos, culturais, linguísticos, arquitecturais e pessoais, mantendo uma base conceptual mas sendo recriado à medida que viaja para novas locais, como um Cadáver Esquisito épico.
"Muitos portugueses da minha geração relatam a história de uma criança olhando para o mapa de Portugal pendurado na sala de aula como se fosse uma cara… a Espanha como se fosse o cabelo e o pescoço… a cara de Portugal vista de perfil, de costas para a terra conhecida, virada para o mar, mar passado, mar novo. Algures na minha genealogia esta experiência ocorreu. Levou-os através de uma massa continental e dois oceanos até ao Havai. A minha mãe olhou para a terra de onde eles vieram, eu olhei para além da terra onde ela me conduziu. Agora, a genealogia torna-se num círculo. Mas será isto um regresso? Um regresso implica uma origem. Mas isto refere-se a múltiplas gerações. Pode a história genealógica de uma pessoa tornar-se numa história pessoal? Pode isto ser um regresso a casa? Será que isto se parece com a nossa casa?"
Página do projecto no site Binaural
"We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time" –T.S. Elliot
"The only real voyage of discovery consists not in seeking new landscapes but in having new eyes." -Proust
"Passageira Australis" is an intermedia and interdisciplinary maritime performance inspired by the journey to define the concept of "home" and migration. The narrative is a partially fictionalized account of the maritime history of Portugal, with a focus on the debate behind whether the Portuguese were the first Europeans to arrive in Australia, based on the 16th century Dieppe maps of "Jave la Grande" and the myth/history of the Mahogany Ship . Within this the project begins to discuss and question the idea and importance behind being The First, and an interweaving of the artist's own experience being in the country for the First time. Context specific in varying historical, cultural, lingual, architectural, and personal aspects, the project has a conceptual anchor, but will always be born new as it travels to different locations and through different situations as an epic Exquisite Corpse. The Australian version includes an intermedia and interdisciplinary performance in collaboration with Melbourne based dancer and artist Michaela Pegum, who will navigate though an interactive sound and video narrative map following the possible "Discovery" route from Europe to Australia, based on a task based movement score developed by Colbert and New York based movement researcher Wanda Gala. The soundtrack, developed with Portuguese sound artist Rui Costa, will reveal a timeline based on the impact on flora, fauna, and overall soundscape on both countries, while the narrative is sung both on dry land and underwater by Estonia vocalist Anna Hints. Elements from the Portuguese version will blend within the Australian version within the context of an Exquisite Corpse, including video, sound and song, text, and video. This project is possible due to the support of its producers, Binaural/Nodar, funding from DGArtes in Portugal, research and historic map access and support with the Victoria State Library, and much support and generosity from the iAir program at RMIT in Melbourne.
Passageira em Casa / Teatro Viriato residency performance
"Passageira em Casa" presented at Teatro Viriato, Viseu, Portugal
Project "Passageira em Casa" at the Instituto Superior da Maia, Porto, Portugal
"Passageira da Água", mixed down narrative soundtrack from "Passageira em Casa" presented at Sound Devices, Dublin, Ireland
iAir artist-in-residency at the Royal Melbourne Institute of Technology with the interdisciplinary performance "Passageira australis", Melbourne, Australia
Guest Lecturer and Visiting artist on Acoustic Ecology and "Passageira em Casa" in Sound Studies and Film and Video departments at SUNY Binghamton, Binghamton, NY, US
Experimental Intermedia, Nova Iorque, EUA
Fabrica da Polvora, Oeiras, PT
Performas, Aveiro, PT
iAir Royal Melbourne Institute of Technology, Melbourne, Australia
Re.al, Lisboa, PT


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text:
10-15 posts to put links, that would be nice.
It really isn't that big a deal tbh. you can still just wait the extra 5 minutes to get the rights haha
It's for security so you nerds can't be spamming your porn links everywhere.
I got one question for you.
Where the hood at?
Tiocfaidh ár lá
20 POST to PM someone is also irritating, however rules are rules mate.
Haha poor guy, I can somewhere relate :'), but we just have to wait until we have more posts!
Maybe 20 posts would be great ?
Pretty sure this is so bots/people cant advertise/spam outside links
Founder and Creator of 'Realm of Fate'
Donating for rank? Email: firstname.lastname@example.com ; Choose the 'Send money to friends or family' option or else money won't be sent to me until after a month, it will just be pending in my balance, and I need money to pay for vps and keep the server running! Contact me via Skype (below if you haven't added me already) if you have donated!
Donation rank costs $20, All commands and donor chat color.
20 post, is easy to get. You don't have to spam, but respond to people in General is a way
I had the same problem. I wanted to start my first post to be a helpful one with a detailed video I made for this site. NOPE. Instead I get to spam until I can post it. Like really? You're not decreasing spam, only promoting it. If I can pass a captcha to join the site, I should be good.


text:
We're looking for quality crabcakes -- not the Phillips mystery-variety, or anything deepfried, but pan-fried ones with big chunks of crab, bits of onion, etc. and not a lot of filler. Sort of like what you would get at Legal Seafoods back East, if that means anything.
We've gotten burned too many times and are hoping for some serious recommendations.


text:
COOPERSTOWN, N.Y (WJBF/AP).- Singing legend, Sharon Jones, has passed away at the age of 60.
The North Augusta native, known for her outstanding musical abilities, passed away Friday night from pancreatic cancer.
Her husband's Facebook post says she was surrounded by friends and family, including members of her world renowned group–the Dap Kings.
Jones was diagnosed with pancreatic cancer in 2013.
Her story was told this year in a Barbara Kopple documentary called "Miss Sharon Jones!"
Jones was a 2014 Grammy Award nominee for her album "Give the People What They Want."
NewsChannel 6's sympathies are with all those who knew and loved Sharon Jones.


text:
Santa Rosa Ballroom: 12,935 SQ. FT.; including pre-function space
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Our beautiful venue and team of wedding coordinators make all your dreams come true
Our gorgeous location in sunny Southern California is the ideal place to say "I do." Whether you desire an intimate gathering for 50 of your closest friends and family members or an elaborate celebration for up to 850 guests, we will orchestrate it with grace and style.
We offer 36,000 square feet of flexible event space, including two stunning high-ceiling ballrooms, which are exquisite settings for a sit-down dinner. A scenic outdoor patio is the perfect backdrop for wedding photos, the ceremony itself, or a cocktail reception. Collaborate with our chef on a special customized menu and utilize our attentive team of wedding specialists to finesse all the details of your special day. Inquire about special group rates in our 376 spacious rooms and suites, thoughtfully appointed with extras your guests will love.
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text:
Bracknell, United Kingdom (PressExposure) August 19, 2009 -- UK Jazz Radio has announced that Nora McCarthy, an important force in the advanced New York jazz vocal scene, has joined the Presenter team at the 24 hour jazz radio station.
Nora McCarthy is a highly original singer, lyricist, composer, poet and educator. She and her various groups work at the top jazz venues in New York and elsewhere in the world.
In her programme, being broadcast several times across the week to give everyone the opportunity to catch the show, Nora will present a vast array of vocal and instrumental jazz recordings from early jazz to the avant-garde and free music art forms featuring those artists currently on the cutting edge of the scene today as well as those legendary artists whose contributions to the music are undeniable.
Having performed with many jazz legends, from Wilson Pickett to Jorge Sylvester, Nora will share rare anecdotes and stories with listeners and music fans, especially jazz devotees, are sure to enjoy this exciting journey into the music that is synonymous with New York City.
Brian Soundy, Music Director of UK Jazz Radio, said: âOur impressive Presenter line-up is essentially UK-based broadcasters but we approached Nora as we knew that she could bring a unique contribution to the station. This is very original format and a very original show and is exclusive to UK Jazz Radio.â
If you are anxious to hear the new edition of Noraâs show, âNora McCarthy's New York Jazz Expressionsâ, as soon as it is broadcast for the first time each week, then listen in every Friday 10pm at http://www.ukjazzradio.com


text:
15/08/2014 Computer - IT - Webs
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Fractal Based Management of Heterogeneous Data Streams
Efficient handling of huge amount of data stream is become mandatory in various domains such as business, finance, sensor networks, etc. Come through these data streams poses challenges those are distinct from those addressed by orthodox database management systems. The enormous increase of Sensor Networks, GPS enabled devices and RFIDs results in highly impulsive environments where objects as well as queries are continuously moving. This paper presents a continuous query processing designed specifically for highly dynamic environments. This paper presents a data stream indexing system that satisfies the requirements in evolving data streams.
Provided by: International Journal of Computer Science and Information Technologies Topic: Mobility Date Added: Jul 2012 Format: PDF


text:
P-3.4 Wed. October 26, 2005. Motivation Quantify the impact of interannual SST variability on the mean and the spread of Probability Density Function (PDF) of seasonal atmospheric means. Abstract
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Analysis of Interannual variability in atmospheric signal and noise with SSTsBhaskar Jha and Arun KumarClimate Prediction Center, NCEP/NOAA, Camp Springs, MD-20746
Fig. 6. (Left panel) warm composite of spread, and (right panel) cold composite of spread.
Fig. 3. (Left panel) observed seasonal mean 200 hPa height regressed against the observed Nino 3.4 SSTs variability and (right panel) same but for the AGCM ensemble means.
Analysis of inter-annual variability in the mean and spread and its relative contributions of changes in the mean and spread to seasonal predictability
Fig. 7. (Left panel) The difference of spread of warm composite and mean spread and (right panel) same as left panel except for cold composite.
Fig. 4. (Left panel) observed 200 hPa height warm composite and (right panel) for the AGCMs. The warm SST events are defined as those when the Nino 3.4 SST index is at least one standard deviation above normal.
Fig. 1. DJF total variability of 200 hPa seasonal mean heights. Total variance is computed from the variance of all DJF for the period of 1950-2000. (Left panel) observation and (right panel) Eight AGCM. Units are in meters**2.0.
Fig. 8. Signal to Noise ratio of 200 hPa height for eight AGCMs.
Fig. 5. As in Fig. 4, but for cold composite. The cold SST events are defined as those when the Nino 3.4 SST index is at least one standard deviation below normal.
Fig. 2. Left panel shows the external variability of 200 hPa. External variability is computed from the ensemble mean of all DJFs. Right panel shows the internal variability (spread). Units are in meters**2.0. Note the difference in magnitude of the external and the internal variability.