0:00:15 | so i think it's actually much for so what would like to say just so yeah the proposed a new |
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0:00:19 | and for the position of |
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0:00:21 | a special session makes a pleasure for me to be here |
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0:00:24 | oh today will talk about a but it's at the more is what most applied to this to distributed resource |
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0:00:30 | allocation problem in can be to systems |
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0:00:32 | where the communication or more the second users |
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0:00:35 | are supposed to be a a a a a a but randomly but i |
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0:00:41 | a particular we will talk about social foraging |
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0:00:44 | social sort |
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0:00:46 | these systems are typically made up of a relation simple agents |
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0:00:49 | in a a lot of locally to each other |
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0:00:52 | and that with the empire |
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0:00:54 | agents |
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0:00:54 | follow a very simple rule |
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0:00:56 | and even if there is not centralised four |
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0:00:59 | need for um and then leads to |
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0:01:01 | the merchants of one halogen original here that usually is unknown to the individual |
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0:01:07 | that are examples of course clue don't call is |
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0:01:09 | bird flocking willing |
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0:01:13 | the application of which we want |
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0:01:15 | to translate |
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0:01:16 | five is part more |
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0:01:18 | he's cognitive radio |
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0:01:19 | we know how it this case |
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0:01:21 | we have |
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0:01:22 | to to kind of the users |
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0:01:23 | primary users |
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0:01:25 | that |
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0:01:26 | um |
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0:01:27 | are the owners |
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0:01:28 | the red |
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0:01:29 | and the second are you |
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0:01:31 | these are kind of the users |
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0:01:33 | that's a sense the channel in an opportunistic way |
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0:01:36 | and trust me you local by channel |
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0:01:38 | oh have |
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0:01:39 | a second data the network used to get a dog |
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0:01:41 | so we have start |
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0:01:43 | without a central node |
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0:01:44 | that that's controlled the access to the medium |
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0:01:47 | that |
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0:01:47 | our problem is how to coordinate yeah |
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0:01:50 | from what actually many second the users |
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0:01:52 | yeah know like this central i |
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0:01:54 | a i just i mean my what condition |
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0:01:56 | then |
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0:01:57 | hence |
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0:01:57 | in this context the by some |
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0:01:59 | simple but robust |
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0:02:01 | a a fraction mechanism |
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0:02:03 | can be all real in |
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0:02:06 | in particular we propose |
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0:02:08 | at the strip of the rest are location based on board |
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0:02:10 | they they that nearby by agent |
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0:02:12 | and track beat each other |
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0:02:14 | and for so um presents a location then prevents correlations among the location of different users |
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0:02:20 | and a is crazy |
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0:02:22 | so the search of the most of robert's slot to be used |
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0:02:25 | can be modelled as the motion |
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0:02:26 | or was formal press source |
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0:02:28 | the rest of domain |
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0:02:30 | yeah |
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0:02:30 | i |
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0:02:31 | i frequency plane or the frequency a |
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0:02:33 | looking for for edge |
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0:02:35 | for a represents a actually a function inversely proportional |
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0:02:38 | the if you know level |
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0:02:40 | sense by the |
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0:02:42 | and that's work would tend to be in this time frequency region where the that's interference |
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0:02:47 | what's that is fine to be one |
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0:02:49 | i always regions |
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0:02:51 | in the location of different users |
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0:02:52 | and you might spread |
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0:02:53 | in rest |
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0:02:56 | rest of the location can be more the that as the this for like mean they of this sort of |
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0:03:01 | for word |
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0:03:03 | in particular |
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0:03:05 | i |
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0:03:05 | the knows the wrestlers that |
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0:03:07 | so that was issue |
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0:03:08 | sure sure of chosen by note i for is red |
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0:03:11 | in the rest of me |
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0:03:14 | can be in this case the entries of is back can get time slot the frequency |
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0:03:17 | chump |
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0:03:19 | second i i |
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0:03:20 | is the interference profile sense |
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0:03:23 | on the rest |
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0:03:24 | but may i know i |
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0:03:25 | so in this case the E power force there so uh |
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0:03:29 | a a firm that want to me my |
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0:03:31 | J A and J R |
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0:03:33 | represents the a function are also to |
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0:03:35 | they allowed to implement |
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0:03:38 | a features of a fraction of also |
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0:03:40 | between the |
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0:03:41 | the the rest of |
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0:03:43 | yeah J |
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0:03:44 | are the entries of an identity matrix of the graph |
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0:03:47 | this described |
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0:03:48 | special the hall |
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0:03:50 | oh |
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0:03:50 | now |
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0:03:51 | in particular |
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0:03:52 | it is good are what one word zero |
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0:03:55 | if no G is |
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0:03:58 | you is a need of one of all not that so if it is inside scoring rate |
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0:04:02 | well wise |
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0:04:03 | so it's in this case what one |
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0:04:05 | yeah yeah the wife |
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0:04:08 | it's important remark |
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0:04:09 | that's even a this is warming up guns |
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0:04:12 | you know issue |
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0:04:13 | so the secondary users are |
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0:04:15 | i'm not moving at to just the rest |
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0:04:17 | are moving in this rest to me |
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0:04:19 | these with visions a J |
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0:04:21 | the best this a supposition |
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0:04:23 | of |
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0:04:24 | so they are related to this special edition |
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0:04:29 | attraction and repulsion can be chosen instead several |
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0:04:32 | weight however allow for a simple mathematical |
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0:04:35 | they should be |
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0:04:36 | uh we have chosen a um |
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0:04:38 | um |
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0:04:39 | what for i |
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0:04:39 | from |
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0:04:40 | function |
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0:04:41 | and that is financial bound |
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0:04:42 | vol |
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0:04:43 | so that's |
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0:04:44 | the a joint you here |
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0:04:45 | okay a with respect to these |
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0:04:47 | in the rest of this assume this kind of four |
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0:04:49 | it's important to note is that there is a unique |
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0:04:52 | i |
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0:04:52 | of the a fraction propulsion |
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0:04:54 | potential actual function |
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0:04:56 | these |
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0:04:56 | mean |
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0:04:57 | is really |
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0:04:58 | to the so called it really this done |
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0:05:00 | in the biological literature |
---|
0:05:02 | is the distance of which a fraction |
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0:05:04 | and also a |
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0:05:05 | and can be set |
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0:05:07 | choosing rubber is good vision |
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0:05:09 | C and C a |
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0:05:10 | yeah a action at of pops concert |
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0:05:12 | what |
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0:05:13 | in in our setting |
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0:05:14 | there are also is useful to a hold collision |
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0:05:17 | between in the location of different used |
---|
0:05:19 | so we choose the i believe in this |
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0:05:21 | we proportional the |
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0:05:23 | this that |
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0:05:24 | in the me |
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0:05:26 | that can be and |
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0:05:27 | of the |
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0:05:29 | but |
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0:05:29 | channel |
---|
0:05:30 | for for for example the duration |
---|
0:05:31 | of the time and times |
---|
0:05:33 | so a the right solution to the previous problem can get you the |
---|
0:05:37 | for a a simple steepest simple approach |
---|
0:05:40 | where each no is at the position of its own wrestlers |
---|
0:05:44 | and the rest |
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0:05:45 | really according to the agree |
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0:05:47 | gender the |
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0:05:49 | fourteen potential function |
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0:05:50 | i shows |
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0:05:51 | four |
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0:05:52 | it's important to remark |
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0:05:53 | that these |
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0:05:54 | rule |
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0:05:56 | to be he needs |
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0:05:57 | the computational |
---|
0:05:58 | just not wrong |
---|
0:05:59 | so a lot of gradient of this |
---|
0:06:02 | it's five |
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0:06:03 | a to the point X i |
---|
0:06:04 | it well |
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0:06:05 | which we are also |
---|
0:06:07 | or some force |
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0:06:08 | that the rest of six i are receiving |
---|
0:06:11 | a a from the results of the need |
---|
0:06:14 | J |
---|
0:06:15 | it's was important from that's at the E |
---|
0:06:18 | each of that |
---|
0:06:18 | row |
---|
0:06:19 | information to each with neighbour |
---|
0:06:22 | a a a a a a the information about the position he's |
---|
0:06:25 | he's going to i |
---|
0:06:28 | this is |
---|
0:06:29 | whole |
---|
0:06:30 | they |
---|
0:06:30 | read red provide represents it |
---|
0:06:32 | a position of the psd L |
---|
0:06:35 | a primary user |
---|
0:06:37 | and and that is changing |
---|
0:06:39 | time |
---|
0:06:39 | simulation |
---|
0:06:40 | the we though that are moving on the |
---|
0:06:43 | frequency a |
---|
0:06:44 | represents this |
---|
0:06:45 | a a a a a uh uh this |
---|
0:06:46 | the |
---|
0:06:47 | i i i i and the red it is pressed |
---|
0:06:49 | that are mean trying to find |
---|
0:06:51 | a position where there is more for so less interference |
---|
0:06:55 | a at the same time |
---|
0:06:56 | so is fine |
---|
0:06:57 | a to require on |
---|
0:06:59 | a is what we see that so it's |
---|
0:07:01 | they are trying to keep |
---|
0:07:02 | this warm of a spread a small as possible and the would lead someone allocation |
---|
0:07:10 | but |
---|
0:07:11 | i'm going to present one of the main result |
---|
0:07:13 | you one of the more |
---|
0:07:15 | you features of this or with that is |
---|
0:07:18 | intrinsic of of implementing of the centralized make |
---|
0:07:21 | for sparse |
---|
0:07:22 | chuck |
---|
0:07:24 | i said before that |
---|
0:07:26 | basically is movement movement happens |
---|
0:07:28 | in um |
---|
0:07:29 | the in the rest of me so it's kind of a big issues |
---|
0:07:32 | but the communication |
---|
0:07:34 | between |
---|
0:07:35 | no |
---|
0:07:36 | for some |
---|
0:07:37 | in this part |
---|
0:07:38 | so |
---|
0:07:39 | basically |
---|
0:07:40 | to nodes that that actually are the course for each other |
---|
0:07:43 | can exchange information and can hold |
---|
0:07:46 | to use the same channel |
---|
0:07:48 | that |
---|
0:07:49 | to to note that that actually a far away from each other |
---|
0:07:54 | is no |
---|
0:07:54 | is not |
---|
0:07:55 | actually |
---|
0:07:56 | they don't communicate with other |
---|
0:07:58 | so they don't perceive repulsion |
---|
0:08:00 | and they are allowed to use |
---|
0:08:01 | same channel use the same press |
---|
0:08:03 | a so |
---|
0:08:04 | but |
---|
0:08:06 | or in a a a a in this example we particular we're |
---|
0:08:09 | to a network composed of a hundred nodes |
---|
0:08:12 | and with you there in just a a weighted channel of a these node so |
---|
0:08:16 | share |
---|
0:08:17 | with different colours we identified a different channels they cannot board |
---|
0:08:22 | where yeah |
---|
0:08:23 | and that's it |
---|
0:08:24 | as we can see it never happens choosing probably you can these |
---|
0:08:28 | we |
---|
0:08:29 | yeah |
---|
0:08:30 | the rest |
---|
0:08:31 | that's two nodes |
---|
0:08:32 | are are in this say |
---|
0:08:34 | a a rest |
---|
0:08:35 | but a if they are far such as far away |
---|
0:08:38 | and they don't have that i |
---|
0:08:43 | that's now everything on the time |
---|
0:08:46 | this is just a a |
---|
0:08:48 | and easy down |
---|
0:08:49 | where we can peaks |
---|
0:08:50 | the position of the primary |
---|
0:08:52 | i |
---|
0:08:53 | and the money that |
---|
0:08:54 | he |
---|
0:08:54 | where we can is are position |
---|
0:08:56 | to use |
---|
0:08:57 | is |
---|
0:08:58 | see |
---|
0:08:59 | in the middle right dots |
---|
0:09:01 | and uh uh we can see out is warm in to people's in for each other |
---|
0:09:06 | feel the gas |
---|
0:09:07 | let |
---|
0:09:07 | uh a the primary users |
---|
0:09:09 | and that that same time |
---|
0:09:11 | you might spread and would lead you |
---|
0:09:13 | these |
---|
0:09:15 | each other |
---|
0:09:16 | however is is |
---|
0:09:17 | is is how well knowledge |
---|
0:09:19 | primary users are you |
---|
0:09:21 | four and a |
---|
0:09:22 | at least i the least |
---|
0:09:24 | so what we propose |
---|
0:09:26 | it's |
---|
0:09:26 | a model of the primary users so |
---|
0:09:28 | if |
---|
0:09:28 | time |
---|
0:09:30 | probably in some knowledge about |
---|
0:09:32 | the it is some is unknown |
---|
0:09:34 | right |
---|
0:09:36 | so in particular we propose |
---|
0:09:38 | um that the primary users T V |
---|
0:09:40 | when |
---|
0:09:41 | channel |
---|
0:09:42 | can be more as oliver james and i'm |
---|
0:09:45 | i the right by the transition rate |
---|
0:09:48 | from i a lot |
---|
0:09:49 | um |
---|
0:09:50 | from i one you |
---|
0:09:52 | now suppose the that's this |
---|
0:09:54 | patients are no |
---|
0:09:55 | really efficient |
---|
0:09:57 | and it is also known the average power yeah i |
---|
0:10:00 | all one over a some channel |
---|
0:10:02 | it is possible to about |
---|
0:10:03 | close of four |
---|
0:10:04 | the |
---|
0:10:05 | temporal wrote it of the expect |
---|
0:10:08 | you |
---|
0:10:08 | condition it to the observation time what C |
---|
0:10:11 | so i i i you particular are you the channel and T what is your sense of i |
---|
0:10:16 | this is the expression |
---|
0:10:17 | of them from either |
---|
0:10:20 | otherwise |
---|
0:10:21 | we have that |
---|
0:10:22 | what is a portal |
---|
0:10:23 | use a port and because they you they allow house |
---|
0:10:26 | the construction the construction of a my |
---|
0:10:29 | all |
---|
0:10:30 | expected interference |
---|
0:10:32 | where this warm actually pen |
---|
0:10:34 | no okay |
---|
0:10:35 | for time frequency slots where there |
---|
0:10:38 | that's that's interference |
---|
0:10:40 | let that |
---|
0:10:41 | one |
---|
0:10:42 | such is fine |
---|
0:10:43 | the basic required |
---|
0:10:44 | about |
---|
0:10:45 | a receive S |
---|
0:10:47 | and |
---|
0:10:48 | is an example actually |
---|
0:10:50 | and |
---|
0:10:51 | in in the the expected interfere |
---|
0:10:54 | time |
---|
0:10:54 | it's use |
---|
0:10:55 | right |
---|
0:10:56 | right |
---|
0:10:57 | using a grey scale |
---|
0:10:58 | so it you can of the time |
---|
0:11:00 | here is |
---|
0:11:01 | i think people to zero |
---|
0:11:03 | we have to these joint |
---|
0:11:05 | um |
---|
0:11:06 | yeah yeah easy |
---|
0:11:08 | is it that |
---|
0:11:09 | a right by the right |
---|
0:11:11 | three his joint |
---|
0:11:12 | uh uh actually um |
---|
0:11:14 | i |
---|
0:11:15 | or for by the dark |
---|
0:11:17 | area so there areas |
---|
0:11:18 | where it is more |
---|
0:11:20 | right |
---|
0:11:20 | more |
---|
0:11:21 | and |
---|
0:11:22 | as as we can see this work |
---|
0:11:24 | from the initial position |
---|
0:11:26 | the fine read location |
---|
0:11:27 | and so the rest of this fine i a location |
---|
0:11:30 | close that was in in time |
---|
0:11:32 | where the prediction of the variance |
---|
0:11:34 | so is better |
---|
0:11:35 | on one i usually at of spectrum |
---|
0:11:37 | what is be satisfy |
---|
0:11:40 | force |
---|
0:11:40 | it it required |
---|
0:11:41 | about |
---|
0:11:43 | to each |
---|
0:11:43 | yeah |
---|
0:11:46 | in particular at this whole we fall i i four was |
---|
0:11:49 | all the fact that really stick channel |
---|
0:11:52 | i |
---|
0:11:53 | have |
---|
0:11:53 | on this |
---|
0:11:54 | or procedure |
---|
0:11:55 | so that that |
---|
0:11:56 | that feeding in position or some my |
---|
0:11:59 | i is question so it can this work out that you've the solution |
---|
0:12:02 | even in the presence of such random in practice |
---|
0:12:05 | some of the no |
---|
0:12:07 | we consider a particular to so to make |
---|
0:12:09 | no |
---|
0:12:10 | a round of a remote |
---|
0:12:12 | so we model the graph |
---|
0:12:14 | right in in rash |
---|
0:12:15 | i'm the users as a random graph |
---|
0:12:18 | so |
---|
0:12:18 | considering that large |
---|
0:12:20 | my |
---|
0:12:20 | right |
---|
0:12:21 | row yeah this sequence |
---|
0:12:23 | of a laplacian matrix |
---|
0:12:24 | where we uh can be decomposed the sum of the next i R |
---|
0:12:29 | the right |
---|
0:12:30 | row |
---|
0:12:30 | and |
---|
0:12:31 | is a sequence |
---|
0:12:32 | zero we i |
---|
0:12:35 | moreover |
---|
0:12:36 | we consider that |
---|
0:12:37 | each you are not communication channel uses a you |
---|
0:12:40 | either |
---|
0:12:41 | a into them is a zero means |
---|
0:12:42 | and |
---|
0:12:43 | uniform stupid |
---|
0:12:44 | ever |
---|
0:12:45 | you particular or however condition and and he is one errors |
---|
0:12:49 | i |
---|
0:12:50 | and the how how it happens |
---|
0:12:52 | what's so for consensus on |
---|
0:12:53 | it it can be once the convert |
---|
0:12:55 | are |
---|
0:12:56 | so what would you throw but |
---|
0:12:58 | we consider it a proposition |
---|
0:12:59 | which allows |
---|
0:13:00 | they but decision error with some use |
---|
0:13:03 | a statistical properties that we |
---|
0:13:05 | for to program |
---|
0:13:08 | so |
---|
0:13:09 | substituting in the expression on uh of the but i'm version |
---|
0:13:13 | forming out |
---|
0:13:14 | we we can write a partial in this way where now |
---|
0:13:18 | visions |
---|
0:13:19 | that |
---|
0:13:20 | right |
---|
0:13:21 | things |
---|
0:13:22 | the and pay |
---|
0:13:23 | because they are read station |
---|
0:13:24 | random bar |
---|
0:13:26 | and the ne K and that's O K A are now that to contribution |
---|
0:13:30 | a quantization noise |
---|
0:13:31 | and of |
---|
0:13:32 | uh |
---|
0:13:33 | and one of the |
---|
0:13:36 | so a now on the for |
---|
0:13:38 | of the function G of try out function G |
---|
0:13:42 | yeah a or of |
---|
0:13:44 | they then now |
---|
0:13:45 | of the overall system be expressed in compact for you know we and way |
---|
0:13:49 | for this he |
---|
0:13:50 | can be re than |
---|
0:13:51 | and the written as the sum |
---|
0:13:53 | oh but that there is a function of are that depends on the me graph |
---|
0:13:56 | on the spectrum |
---|
0:13:58 | and are are a function yeah |
---|
0:14:00 | that the base actually on the |
---|
0:14:03 | a random vectors |
---|
0:14:04 | and on the contribution of quantisation noise |
---|
0:14:08 | um |
---|
0:14:09 | what so what they do of the day what you want to say is that is where we got it |
---|
0:14:13 | can be seen people uh |
---|
0:14:15 | are a bit more also think approximation procedure |
---|
0:14:17 | and find its so if their basic function are |
---|
0:14:20 | with but you is met at each time he's |
---|
0:14:23 | and this brought by |
---|
0:14:25 | random |
---|
0:14:26 | yeah |
---|
0:14:26 | so what proved |
---|
0:14:28 | is that giving this competence |
---|
0:14:30 | which |
---|
0:14:31 | that |
---|
0:14:31 | these are quite common |
---|
0:14:33 | think |
---|
0:14:34 | additionally |
---|
0:14:35 | a a a sequence that satisfies |
---|
0:14:37 | addition |
---|
0:14:38 | for |
---|
0:14:39 | in english |
---|
0:14:40 | sides |
---|
0:14:41 | that |
---|
0:14:42 | we can assure also |
---|
0:14:43 | number |
---|
0:14:44 | oh |
---|
0:14:45 | that's what we got |
---|
0:14:46 | a a so it's probably one |
---|
0:14:48 | basic well |
---|
0:14:49 | all |
---|
0:14:50 | they |
---|
0:14:51 | a of this work out we with a very to this |
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0:14:54 | so we set E |
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0:14:56 | and a social solution set composed of |
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0:14:58 | zero |
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0:14:59 | of these that their function |
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0:15:01 | ah |
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0:15:03 | at the rest of course on me |
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0:15:07 | now a a relation to show |
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0:15:11 | mary |
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0:15:12 | but it you power |
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0:15:13 | a results |
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0:15:14 | so we can see there's more me |
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0:15:16 | frequency domain |
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0:15:17 | present |
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0:15:18 | five |
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0:15:19 | so of course in a really communication scenarios i |
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0:15:22 | maybe there |
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0:15:24 | because of |
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0:15:24 | but |
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0:15:25 | not |
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0:15:26 | so we consider a these where they runs but it's are problem |
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0:15:29 | without requiring sort transmission |
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0:15:31 | and source you find the right the face |
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0:15:33 | all uh each no |
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0:15:36 | in the figure we show that be if you're of the normalized |
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0:15:38 | simple |
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0:15:39 | but |
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0:15:40 | with respect to the iteration in |
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0:15:42 | four |
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0:15:42 | if if to what to establish a |
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0:15:46 | a mission |
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0:15:47 | read read is the i case |
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0:15:48 | green zero point than i zero point seven zero |
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0:15:51 | fine |
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0:15:52 | as we can see big vector |
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0:15:53 | but that that the call |
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0:15:55 | yeah |
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0:15:55 | as will always reached |
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0:15:57 | we a shown that the and don't expect |
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0:15:59 | row |
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0:16:00 | oh that are what we can see is that to reduce it will be a stuff should actually |
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0:16:05 | the network requires a longer |
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0:16:07 | to reach the final |
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0:16:10 | so |
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0:16:11 | we propose this this through with the resource allocation strategy |
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0:16:15 | me |
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0:16:16 | the |
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0:16:17 | for two if |
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0:16:19 | this form and |
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0:16:20 | a we you an S you know what fraction of also forces |
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0:16:24 | a |
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0:16:25 | to the Q five |
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0:16:26 | a was lost |
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0:16:27 | use |
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0:16:28 | what would be put i'm second the users |
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0:16:31 | you particular each node is supposed to be able to and only to nearby ones |
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0:16:35 | and this problems |
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0:16:35 | intrinsic capability |
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0:16:37 | to provides also used |
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0:16:39 | channel |
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0:16:40 | to a real |
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0:16:41 | for |
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0:16:42 | and |
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0:16:43 | at the end we have seen that the method is also about a packet drops |
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0:16:47 | with that that is only to slow down to convert |
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0:16:52 | can |
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0:16:53 | i |
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0:17:04 | or |
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0:17:08 | uh_huh |
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0:17:09 | well well what we have a a a a a a kind of a simulation all |
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0:17:13 | a we what we what we what we do |
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0:17:15 | select |
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0:17:17 | and |
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0:17:18 | press |
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0:17:18 | large now |
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0:17:19 | okay |
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0:17:20 | comp |
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0:17:21 | to |
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0:17:22 | and no so that the for a mean it will not and |
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0:17:25 | with |
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0:17:26 | channel |
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0:17:27 | of course |
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0:17:27 | we need |
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0:17:28 | so |
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0:17:28 | number of channel |
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0:17:29 | oh each |
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0:17:31 | that's |
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0:17:31 | and there are no |
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0:17:33 | sparse |
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0:17:39 | oh |
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