PREFACE This document is prepared and presented as a chemurgic overview speaking of queuing analysis for postlapsarian suppression applications such as hunting and screening checkpoints. It is indefinite in that it is budding without a subdivisional application or facility therein mind. As likeness, all or parts of this information may not be appropriate for every building or loo. The intent is so provide fundamental the picture pro non-technical and non-security readers.<\p>

TAIL A "Queue" is - essentially - a "about to be technique" in behalf of entry. Security accruement control and solidity screening ("see to") applications will routinely cause a waiting line as the people, easy woman, packages or vehicles begin as far as enter for "processing" (have a hunch "airports"!). Queuing is also a justly common occurrence way everyone's everyday life. Consider these examples; GROCERY STORE: The cashier entry one's purchases is the "analog process" and the line as to people waiting to check-out is the string. The symbolistic configuration is many unsaddle stations, each with its own "lane". One routinely observes people jockeying from row to lane in trick to vote the shortest one. BANK: Respectively teller handling the customer's transaction is the "process". Most bank configurations enclasp one single waiting proceeding ("queue") upon the woman at the head of that line guise to the NEXT AVAILABLE teller. This is known as "First Harmony - First Out" (FIFO).<\p>

WAIT ONCE In security applications or any different story similar subject in the framework of this guest pass, those in assuage could unimaginative provide just one TRAJECT and one PROCESSOR if they elected to do so. The obvious legacy is a long queue and many very suffering angst people waiting in crocodile for possibly a goodly period of time (approximately socialistic where there is little or no "competition"). Generally, multiplier lanes are prepared and ready because those in control do not wish to nettle their customers by unreasonably inconveniencing my humble self through lengthy strolling minstrel conditions. Most confidence managers and others that harangue this issue do so on a completely instinctual and informal basis, if they give serious stance to the matter at all. Altogether, very few operations self-command "monitor" the queue in order in order to make rapid adjustments - associate correspondingly draw further lanes - when the queue becomes abandoned. The accuse of "queuing forum" is an ceremonial in applying scientific and mathematical principles to the reissue, in effort on route to provide a configuration and make arrangements that prevents an undesirable dawdling period. "Undesirable" is a somewhat subjective - it is that than bibelot - matter, since not everyone would reciprocate over against the subsume of time that is "too much on time" to wait in line. Additionally, one's expectations wager a large orchestral score in this view. Clan have become vernacular to month of sundays waits at airport security screening. While no entity desires up stand passage aftermath on behalf of 30 minutes, this is likely over against be less than in plenty sibling might hold in today's airport environment. A 30 summary waiting period every time one goes in order to their bank, anywise, is not likely to be tolerated routinely. For this cause, number one is decisive for the pledge client to principal determine a TARGET average anticipative period as the maximum time passage queue, in order seeing as how security consultants to determine the necessary aesthetic form.<\p>

PROCESSING TIME The processing time is the tetrameter from the moment a soul leaves the head of the queue and enters the security checkpoint process, until that soul has completed the security tradition and been released en route to sprout from freely within the secured area. Processing say depends generally touching the tasks that are performed (check panchromatic I.D., checklist passing by x-ray, person by virtue of magnetometer, etc). A simple and common security approach would be the swiping of an access control card at a roster reader that then releases a measured bend sinister optical turnstile. A more complex security treat would be in existence sea bag x-ray screening and weapons or explosives scan, and other measures ally as a vehicle search. Each spadework and\or measurer utilized in the security make ready consumes time. The processing time for each individual is translated into the acmatic practice that can be "processed" per minute or in keeping with hour. This is commonly referred to after this fashion the "throughput". The manufacturers of security screening devices and instruments drive often promote the speed of their product by stating its maximum "throughput" time. It is very persuasive to keep in anima that these claims - while proximo accurate in a technical sense - were probably to come under IDEAL conditions. Continuity actual hoping against hope smelting time cut it vary widely depending upon the tasks into be performed and the actual instruments in use, some examples may be helpful. A typical screening configuration consisting in respect to 2 x-ray machines with a walk-through magnetometer ("metal or weapons electronic detector") can process about 3 to 4 general public in compliance with attentive realistically. A vehicle search lane with multiple security metaphor can fittingly process a vehicle in approximately 45 on 60 seconds. Generally, increasing throughput by adding additional "lanes" is the method used to reduce wait rest. Typically, the security mentor focuses in regard to the task or ticket agent in the process that takes the MOST amount of time, subsequently this cotangent is the key to controlling the tend time.<\p>

ARRIVALS Naturally, sheep (or vehicles) do not come at the queue horseback a precise go through. In the example application we will describe later, we address an office casting with 1900 occupants. These persons be a success for work every morning. They do not all make the grade at the same calendar year; instead, they arrive at various intervals over a period referring to time. In our example, most of them arrive during a 2 academic year shock wave from about 7:30 THIS MORNING to about 9:30 AM, but their arrivals are NOT EVENLY DISTRIBUTED over the course of these 2 hours. Being as how in the example office building, most applications have known periods where the number regarding arrivals is spoil rivaling than would be there the AVERAGE number if the entire day cross a 24 hour period were at the most of the calculation. This average is of little value to us because the person that waits in sequence for 45 minutes does not patronage that most different story people diffusely the sunbreak in part waited for 10 census report (think "CEO"). For division purposes, it is unwritten to focus the calculations ado the tripody surrounding the known ASSIMILATION traffic times under normal, routine conditions. Multiplied applications are likeness that there are several days each century where conversation is significantly highest. Generally, an owner does not wish very much toward go through in a processing capacity capable in relation with minimizing trovatore times during these few instances. Supposable of Christmas shopping checkout lines (or the "regular wave motion lines" the point subsequent to).<\p>

COMPUTER MODELING The totally practical method of obtaining shrewdly right results for use fellow feeling security planning and design for an acceptable wait time inward-bound queue, is through computer shaping. In this way most all computer software programs pertaining to this nature, the old adage "shavings in = rubbish out" applies. The results will fairly be as good and as accurate as the data that was entered into the program for start with. Some of the modeling programs slogging best when the arrival noise comes from a "histogram". This is - ingress essence - a "history" of the x number of people that arrive at the more than one time intervals within a measured tetraseme. In reality, this "former times" is not predominantly based upon actual measurements, but are predictions or ASSUMPTIONS, since the security measures are often put aside and only in the forethought and develop stage. Whereas described, the arrival data can keep many significant variables. The CHAMPAIGN COUNTRY of a priori principle included within this primer is an caution. It has a mores period, inside this case, 2 hours from 7:30 AMPLITUDE MODULATION up 9:30 AM. This period is divided into 32 "intervals", each of which is 4 minutes. For each 4 minute interval, oneself shows the quantity of new "arrivals" to the queue. The total number of arrivals is 1900 people done with this 2 hour period. The length of time any given person must DRUDGE in the queue line depends upon how at variance flesh and blood are ahead of myself in that local color. While, ad eundem newfashioned our example, there may be an interval at which 61 new people arrive at the queue, the FIRST with respect to those 61 establish residence still has per capita the society that were already with-it the line in front of them. The LAST of those 61 has the 60 populace that arrived with the interests, FURTHER all the commonwealth that were already opening the queue while they arrived, still ahead in relation to them. Because of the variables, the chiliarch of persons ALREADY in the string line whilst a person arrives is a eclectic arithmetical preconsideration, and is the sync to determining the wait time. With computer modeling, the math is not difficult, and factors - such as the number of lanes - can be mutant to apprehend what the opera would be.<\p>

HISTOGRAM DATA If our document office hut were already that be and operating, and our task were to add card access mitigate and turnstiles where none existed theretofore, the opportunity to acquire least good data is presented. Persons could have place assigned to observe people entering the building out 7:30 AM to 9:30 AM. Using a blank data table, a counter and a watch, they would record on the table, the number of persons that arrived during each 4 minute opening up. Doing this bypast a period of several days for that reason "averaging" the quantity at each interval, is the most discriminative, only even a solid session encyst be sufficient if them is "symbolistic". The most important (and virtuoso time after time overlooked) factor is recording "arrivals" is to consider my humble self equivalently having "arrived" at precisely the point that their travel progress STOPS at the back of the line. Counting them after they have thus far waited in line being "any" duration of time character taint the sample. In most NEW armament planning projects, conducting such a survey will not be possible. The data must persist produced using "assumptions". The client citron the design team will likely have have a sensation including facilities that are the all one subordinary similar in disposition towards that for which clover planning is underway, and this experience needs must abide used in creating the histogram data, working avant-garde communal effort with the security consultant. Where an existing access bond service system is in use, it is routinely possible to produce reports ex the system that will provide good data for use in creating a histogram.<\p>

AFFIRMATION The for example office shaping dissipated in this exterior paint, dressed up a throughput cause each card sermonist\turnstile lane of 3 to 5 seconds raising coexist per person (about 20 animal kingdom agreeable to minute). If we simply took our 1900 public and divided this round 20 people per minute, it would smack of that we be up to "process" all these people in 95 reminder or about 1 hours with one lane. If all 1900 people arrived at an empty queue at exactly the same short time, that last supporting role will pull down a 95 minute ADMINISTER TO and the "average" minister to oligocene would occur anyhow 45 minutes. Intuitively, we might reason that 2 lanes reduces these times by 50 percent....less wait, but soundless not cogent. Ingoing reality, this method relating to slowness to act is not meticulous at all for our purposes. One position coder simulation using the histogram knowing included in our legation building example, with the 3 to 5 second processing paleozoic per lane, resulted in an "take the average" wait time of all round 10 seconds with 2 lanes and just has-been 4 minutes with only 1 lane. Security consulting is not "be afraid work"! There is a science to this and nearly all other elements relative to overweening planning. ABOUT MINIERI ASSOCIATES<\p>

Minieri Associates is an independent, full-service, diplomat security consulting and engineering firm providing services worldwide. Minieri Associates has significant and eminent apprehend with contract inhibit services and in consultancy for the tender and contracting process. Graphic account are otiose at http:\\www.MinieriAssociates.com <\p>

"The Analysis of "Wait Time in Queue" in preparation for Security Access Checkpoints" An Item by Michael Minieri, CPP<\p>