|Product Name||Scotland Yard Files: 150 Years of the CID, 1842-1992|
|Category||Book / Magazine / Publication|
|Amazon.com||Buy on Amazon ~ 0747203717|
|Price New||55.90 US Dollars (curriencies)|
|Price Used||2.70 US Dollars (curriencies)|
|Author||Paul Begg, Keith Skinner|
|Features||Used Book in Good Condition|
|Long Description||As the ingenuity of criminals has developed over time, so have the techniques for catching them. The murderer Dr. Crippen's attempted getaway was foiled by the first use of radio at sea, and fingerprint evidence first secured a conviction as far back as 1902. Keith Skinner, a leading crime historian, and Alan Moss, a former Chief Superintendent, have trawled through the archives and selected twelve such fascinating 'firsts' from the history of the world-famous Scotland Yard - including the first 'wanted' picture in the press, the first successful use of identification parades, and the first conviction based on ballistics evidence. A lively narrative is supported by many previously unpublished images and documents from the Scotland Yard files at London's National Archives.|
|Search Google||by EAN or by Title|
Article of interest
We have been asked a few times why we put a delay on the free data feed access and why someone should pay for the fast data feed access instead of just using the free version.
Put simply, the free data feed is inteded for you to use while testing your application or if you have a very low lookup requirement. You can even use the free version in production if you don't mind the forced delay in getting your databack. But if you need high volume or need fast data lookups all day long, you really do need to pay for a subscription.
The free version of the data feed will deliver a limited number of lookups each day at full speed and at no charge. Just like manual lookups, every user gets this limited number of fast lookups. Unlike manual lookups though, if you lookup the same data more than once with your data feed, it still counts as a lookup and one of your free lookups gets used. Manual lookups get repeat lookups for free. Why? Because the user gets to see our ads again and might click on one to earn us a small amount of money. You don't think we run this site for free do you?
With a subscription, all of your data feed lookups are fast no matter how many you execute in a day. Repeat lookups of the same item still count as a new lookup, but they are still just as fast as all the others. We try to optomize the data feed lookups for the subscribers to deliver the highest speed of data delivery as we can.
We have run some tests under simulated conditions using multiple computers but all using the same account. Each computer was on a separate network with its own route into our server. We did this to see variations in access time and how many lookups could be performed in a day. Each computer in the test hammered our site trying to grab unique data lookups as quickly as possible. To make this work we gave each computer a list of known codes that we knew would return valid data.
On the average, each computer in the test could perform a large number of lookups in a 24 hour period. Although each computer had different results based on the network, time of day and load on our server, over all they were all fairly close.
When in FREE mode, they were able to average 18,000 lookups in a 24 hour period.
When in SUBSCRIPTION mode, they were able to average 129,600 lookps in a 24 hour period.
Our server processed an average of 1,684,800 lookup request during each 24 hour period while testing which is many times higher than our normal daily load. We really torchered the server to see what it could do.
You can see from these numbers that we have the ability to deliver a large amount of data. One of the largest factors in delivering the data is the network communication speed. Due to standard delays in communication, it often takes longer to ask for the data than it does for us to lookup the informaiton.
You should also quickly notice that in FREE mode, the system does a very good job of limiting how many lookups can be done. This is done by forcing a pause between the data request and returning the data to the calling application once the fast lookups are used up. And if you are asking yourself why we would force this type of delay, well it should be clear. We need to make money. It costs money and takes time to keep this site running. If you are making a lot of requests for our data, it is probably because you are trying to make money with your app so why should we not also make some money on the deal? Data feeds don't generate any ad revenue so we have to charge another way.
On the data feed page you can learn more about how the feed works and purchase a subscription if you like.