Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. So the real line is divided in intervals of length $15$ and $45$. One day you come into the store and there are no computers available. Analytics Vidhya App for the Latest blog/Article, 15 Must Read Books for Entrepreneurs in Data Science, Big Data Architect Mumbai (5+ years of experience). The simulation does not exactly emulate the problem statement. The probability distribution of waiting time until two exponentially distributed events with different parameters both occur, Densities of Arrival Times of Poisson Process, Poisson process - expected reward until time t, Expected waiting time until no event in $t$ years for a poisson process with rate $\lambda$. Now \(W_{HH} = W_H + V\) where \(V\) is the additional number of tosses needed after \(W_H\). To assure the correct operating of the store, we could try to adjust the lambda and mu to make sure our process is still stable with the new numbers. In a theme park ride, you generally have one line. For example, suppose that an average of 30 customers per hour arrive at a store and the time between arrivals is . When to use waiting line models? With the remaining probability $q$ the first toss is a tail, and then. What is the expected waiting time measured in opening days until there are new computers in stock? The worked example in fact uses $X \gt 60$ rather than $X \ge 60$, which changes the numbers slightly to $0.008750118$, $0.001200979$, $0.00009125053$, $0.000003306611$. We want $E_0(T)$. &= e^{-\mu(1-\rho)t}\\ }\ \mathsf ds\\ Imagine, you are the Operations officer of a Bank branch. Notice that in the above development there is a red train arriving $\Delta+5$ minutes after a blue train. I will discuss when and how to use waiting line models from a business standpoint. This takes into account the clarification of the the OP in a comment that the correct assumptions to take are that each train is on a fixed timetable independent of the other and of the traveller's arrival time, and that the phases of the two trains are uniformly distributed, $$ p(t) = (1-S(t))' = \frac{1}{10} \left( 1- \frac{t}{15} \right) + \frac{1}{15} \left(1-\frac{t}{10} \right) $$. Today,this conceptis being heavily used bycompanies such asVodafone, Airtel, Walmart, AT&T, Verizon and many more to prepare themselves for future traffic before hand. \lambda \pi_n = \mu\pi_{n+1},\ n=0,1,\ldots, The time spent waiting between events is often modeled using the exponential distribution. But conditioned on them being sold out, the posterior probability of for example being sold out with three days to go is $\frac{\frac14 P_9}{\frac14 P_{11}+ \frac14 P_{10}+ \frac14 P_{9}+ \frac14 P_{8}}$ and similarly for the others. To find the distribution of $W_q$, we condition on $L$ and use the law of total probability: $$, $$ In a 15 minute interval, you have to wait $15 \cdot \frac12 = 7.5$ minutes on average. Here are a few parameters which we would beinterested for any queuing model: Its an interesting theorem. On service completion, the next customer You need to make sure that you are able to accommodate more than 99.999% customers. Total number of train arrivals Is also Poisson with rate 10/hour. Lets dig into this theory now. This is called the geometric $(p)$ distribution on $1, 2, 3, \ldots $, because its terms are those of a geometric series. &= \sum_{n=0}^\infty \mathbb P\left(\sum_{k=1}^{L^a+1}W_k>t\mid L^a=n\right)\mathbb P(L^a=n). &= (1-\rho)\cdot\mathsf 1_{\{t=0\}}+\rho(1-\rho)\sum_{n=1}^\infty\rho^n\int_0^t \mu e^{-\mu s}\frac{(\mu\rho s)^{n-1}}{(n-1)! Thus the overall survival function is just the product of the individual survival functions: $$ S(t) = \left( 1 - \frac{t}{10} \right) \left(1-\frac{t}{15} \right) $$. This is a shorthand notation of the typeA/B/C/D/E/FwhereA, B, C, D, E,Fdescribe the queue. If there are N decoys to add, choose a random number k in 0..N with a flat probability, and add k younger and (N-k) older decoys with a reasonable probability distribution by date. This gives a expected waiting time of $$\frac14 \cdot 7.5 + \frac34 \cdot 22.5 = 18.75$$. As discussed above, queuing theory is a study of long waiting lines done to estimate queue lengths and waiting time. which yield the recurrence $\pi_n = \rho^n\pi_0$. With probability $p$ the first toss is a head, so $Y = 0$. So expected waiting time to $x$-th success is $xE (W_1)$. The expected waiting time for a single bus is half the expected waiting time for two buses and the variance for a single bus is half the variance of two buses. }\\ There is a blue train coming every 15 mins. Every letter has a meaning here. What is the expected waiting time of a passenger for the next train if this passenger arrives at the stop at any random time. With probability $q$, the toss after $X$ is a tail, so $Y = 1 + W^*$ where $W^*$ is an independent copy of $W_{HH}$. Between $t=0$ and $t=30$ minutes we'll see the following trains and interarrival times: blue train, $\Delta$, red train, $10$, red train, $5-\Delta$, blue train, $\Delta + 5$, red train, $10-\Delta$, blue train. Since 15 minutes and 45 minutes intervals are equally likely, you end up in a 15 minute interval in 25% of the time and in a 45 minute interval in 75% of the time. How to react to a students panic attack in an oral exam? Cross Validated is a question and answer site for people interested in statistics, machine learning, data analysis, data mining, and data visualization. Theoretically Correct vs Practical Notation. I was told 15 minutes was the wrong answer and my machine simulated answer is 18.75 minutes. The expected waiting time for a success is therefore = E (t) = 1/ = 10 91 days or 2.74 x 10 88 years Compare this number with the evolutionist claim that our solar system is less than 5 x 10 9 years old. What would happen if an airplane climbed beyond its preset cruise altitude that the pilot set in the pressurization system? Data Scientist Machine Learning R, Python, AWS, SQL. Let $N$ be the number of tosses. (2) The formula is. This gives The second criterion for an M/M/1 queue is that the duration of service has an Exponential distribution. @Aksakal. An average arrival rate (observed or hypothesized), called (lambda). Maybe this can help? With this article, we have now come close to how to look at an operational analytics in real life. of service (think of a busy retail shop that does not have a "take a Suppose we toss the \(p\)-coin until both faces have appeared. I think the approach is fine, but your third step doesn't make sense. where $W^{**}$ is an independent copy of $W_{HH}$. \mathbb P(W>t) = \sum_{n=0}^\infty \sum_{k=0}^n\frac{(\mu t)^k}{k! We can find $E(N)$ by conditioning on the first toss as we did in the previous example. a)If a sale just occurred, what is the expected waiting time until the next sale? It is mandatory to procure user consent prior to running these cookies on your website. For example, if the first block of 11 ends in data and the next block starts with science, you will have seen the sequence datascience and stopped watching, even though both of those blocks would be called failures and the trials would continue. You will just have to replace 11 by the length of the string. Answer. $$, \begin{align} Should I include the MIT licence of a library which I use from a CDN? Once every fourteen days the store's stock is replenished with 60 computers. (1500/2-1000/6)\frac 1 {10} \frac 1 {15}=5-10/9\approx 3.89$$, Assuming each train is on a fixed timetable independent of the other and of the traveller's arrival time, the probability neither train arrives in the first $x$ minutes is $\frac{10-x}{10} \times \frac{15-x}{15}$ for $0 \le x \le 10$, which when integrated gives $\frac{35}9\approx 3.889$ minutes, Alternatively, assuming each train is part of a Poisson process, the joint rate is $\frac{1}{15}+\frac{1}{10}=\frac{1}{6}$ trains a minute, making the expected waiting time $6$ minutes. Waiting lines can be set up in many ways. \frac15\int_{\Delta=0}^5\frac1{30}(2\Delta^2-10\Delta+125)\,d\Delta=\frac{35}9.$$. How can the mass of an unstable composite particle become complex? (f) Explain how symmetry can be used to obtain E(Y). Calculation: By the formula E(X)=q/p. In this article, I will bring you closer to actual operations analytics usingQueuing theory. @whuber I prefer this approach, deriving the PDF from the survival function, because it correctly handles cases where the domain of the random variable does not start at 0. One way is by conditioning on the first two tosses. Would the reflected sun's radiation melt ice in LEO? Sign Up page again. With probability \(p\) the first toss is a head, so \(M = W_T\) where \(W_T\) has the geometric \((q)\) distribution. Take a weighted coin, one whose probability of heads is p and whose probability of tails is therefore 1 p. Fix a positive integer k and continue to toss this coin until k heads in succession have resulted. This is the last articleof this series. x = E(X) + E(Y) = \frac{1}{p} + p + q(1 + x) Consider a queue that has a process with mean arrival rate ofactually entering the system. Possible values are : The simplest member of queue model is M/M/1///FCFS. I think that the expected waiting time (time waiting in queue plus service time) in LIFO is the same as FIFO. In a 45 minute interval, you have to wait $45 \cdot \frac12 = 22.5$ minutes on average. Thanks to the research that has been done in queuing theory, it has become relatively easy to apply queuing theory on waiting lines in practice. It only takes a minute to sign up. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Let's return to the setting of the gambler's ruin problem with a fair coin. With probability \(p^2\), the first two tosses are heads, and \(W_{HH} = 2\). rev2023.3.1.43269. Answer. \begin{align} And the expected value is obtained in the usual way: $E[t] = \int_0^{10} t p(t) dt = \int_0^{10} \frac{t}{10} \left( 1- \frac{t}{15} \right) + \frac{t}{15} \left(1-\frac{t}{10} \right) dt = \int_0^{10} \left( \frac{t}{6} - \frac{t^2}{75} \right) dt$. by repeatedly using $p + q = 1$. You are expected to tie up with a call centre and tell them the number of servers you require. A is the Inter-arrival Time distribution . Dave, can you explain how p(t) = (1- s(t))' ? It is well-known and easy to show that the expected waiting time until every spot (letter) appears is 14.7 for repeated experiments of throwing a die with probability . It includes waiting and being served. Answer: We can find \(E(N)\) by conditioning on the first toss as we did in the previous example. Can I use a vintage derailleur adapter claw on a modern derailleur. Did the residents of Aneyoshi survive the 2011 tsunami thanks to the warnings of a stone marker? I am probably wrong but assuming that each train's starting-time follows a uniform distribution, I would say that when arriving at the station at a random time the expected waiting time for: Suppose that red and blue trains arrive on time according to schedule, with the red schedule beginning $\Delta$ minutes after the blue schedule, for some $0\le\Delta<10$. The formulas specific for the M/D/1 case are: When we have c > 1 we cannot use the above formulas. In the problem, we have. You could have gone in for any of these with equal prior probability. This means that we have a single server; the service rate distribution is exponential; arrival rate distribution is poisson process; with infinite queue length allowed and anyone allowed in the system; finally its a first come first served model. So the average wait time is the area from $0$ to $30$ of an array of triangles, divided by $30$. &= e^{-(\mu-\lambda) t}. Even though we could serve more clients at a service level of 50, this does not weigh up to the cost of staffing. And at a fast-food restaurant, you may encounter situations with multiple servers and a single waiting line. With probability $q$, the first toss is a tail, so $W_{HH} = 1 + W^*$ where $W^*$ is an independent copy of $W_{HH}$. At what point of what we watch as the MCU movies the branching started? With probability 1, $N = 1 + M$ where $M$ is the additional number of tosses needed after the first one. In terms of service times, the average service time of the latest customer has the same statistics as any of the waiting customers, so statistically it doesn't matter if the server is treating the latest arrival or any other arrival, so the busy period distribution should be the same. In tosses of a \(p\)-coin, let \(W_{HH}\) be the number of tosses till you see two heads in a row. How many trains in total over the 2 hours? }e^{-\mu t}\rho^n(1-\rho) Asking for help, clarification, or responding to other answers. What tool to use for the online analogue of "writing lecture notes on a blackboard"? Let's find some expectations by conditioning. So, the part is: Hence, it isnt any newly discovered concept. $$ By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. How can the mass of an unstable composite particle become complex? (c) Compute the probability that a patient would have to wait over 2 hours. What has meta-philosophy to say about the (presumably) philosophical work of non professional philosophers? What's the difference between a power rail and a signal line? With probability \(q\) the first toss is a tail, so \(M = W_H\) where \(W_H\) has the geometric \((p)\) distribution. This means that the duration of service has an average, and a variation around that average that is given by the Exponential distribution formulas. This is intuitively very reasonable, but in probability the intuition is all too often wrong. How to increase the number of CPUs in my computer? By using Analytics Vidhya, you agree to our, Probability that the new customer will get a server directly as soon as he comes into the system, Probability that a new customer is not allowed in the system, Average time for a customer in the system. Let's call it a $p$-coin for short. Answer. Finally, $$E[t]=\int_x (15x-x^2/2)\frac 1 {10} \frac 1 {15}dx= Necessary cookies are absolutely essential for the website to function properly. - Andr Nicolas Jan 26, 2012 at 17:21 yes thank you, I was simplifying it. D gives the Maximum Number of jobs which areavailable in the system counting both those who are waiting and the ones in service. = 1 + \frac{p^2 + q^2}{pq} = \frac{1 - pq}{pq}
To this end we define T as number of days that we wait and X Pois ( 4) as number of sold computers until day 12 T, i.e. Do the trains arrive on time but with unknown equally distributed phases, or do they follow a poisson process with means 10mins and 15mins. The logic is impeccable. \mathbb P(W>t) &= \sum_{k=0}^\infty\frac{(\mu t)^k}{k! $$, $$ Keywords. $$ Clearly you need more 7 reps to satisfy both the constraints given in the problem where customers leaving. With probability 1, at least one toss has to be made. Tip: find your goal waiting line KPI before modeling your actual waiting line. Suspicious referee report, are "suggested citations" from a paper mill? I think that the expected waiting time (time waiting in queue plus service time) in LIFO is the same as FIFO. Examples of such probabilistic questions are: Waiting line modeling also makes it possible to simulate longer runs and extreme cases to analyze what-if scenarios for very complicated multi-level waiting line systems. $$. This means that the passenger has no sense of time nor know when the last train left and could enter the station at any point within the interval of 2 consecutive trains. The store is closed one day per week. Waiting till H A coin lands heads with chance $p$. Could you explain a bit more? Can non-Muslims ride the Haramain high-speed train in Saudi Arabia? &= (1-\rho)\cdot\mathsf 1_{\{t=0\}}+(1-\rho)\cdot\mathsf 1_{\{t=0\}} + \sum_{n=1}^\infty (1-\rho)\rho^n \int_0^t \mu e^{-\mu s}\frac{(\mu s)^{n-1}}{(n-1)! There are alternatives, and we will see an example of this further on. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Does With(NoLock) help with query performance? Planned Maintenance scheduled March 2nd, 2023 at 01:00 AM UTC (March 1st, M/M/1 queue with customers leaving based on number of customers present at arrival. Connect and share knowledge within a single location that is structured and easy to search. But 3. is still not obvious for me. $$ It follows that $W = \sum_{k=1}^{L^a+1}W_k$. The average response time can be computed as: The average time spent waiting can be computed as follows: To give a practical example, lets apply the analysis on a small stores waiting line. Waiting line models can be used as long as your situation meets the idea of a waiting line. So this leads to your Poisson calculation: it will be out of stock after $d$ days with probability $P_d=\Pr(X \ge 60|\lambda = 4d) = \displaystyle \sum_{j=60}^{\infty} e^{-4d}\frac{(4d)^{j}}{j! }\ \mathsf ds\\ $$ @Tilefish makes an important comment that everybody ought to pay attention to. In order to do this, we generally change one of the three parameters in the name. This idea may seem very specific to waiting lines, but there are actually many possible applications of waiting line models. Dealing with hard questions during a software developer interview. The following example shows how likely it is for each number of clients arriving if the arrival rate is 1 per time and the arrivals follow a Poisson distribution. . &= \sum_{n=0}^\infty \mathbb P(W_q\leqslant t\mid L=n)\mathbb P(L=n)\\ What if they both start at minute 0. x= 1=1.5. Do share your experience / suggestions in the comments section below. Assume for now that $\Delta$ lies between $0$ and $5$ minutes. The marks are either $15$ or $45$ minutes apart. There's a hidden assumption behind that. &= \sum_{k=0}^\infty\frac{(\mu t)^k}{k! Here are the possible values it can take: C gives the Number of Servers in the queue. We assume that the times between any two arrivals are independent and exponentially distributed with = 0.1 minutes. I hope this article gives you a great starting point for getting into waiting line models and queuing theory. The gambler starts with $\$a$ and bets on a fair coin till either his net gain reaches $\$b$ or he loses all his money. X=0,1,2,. \mathbb P(W>t) = \sum_{n=0}^\infty \sum_{k=0}^n\frac{(\mu t)^k}{k! as before. Answer 1. It has to be a positive integer. Therefore, the probability that the queue is occupied at an arrival instant is simply U, the utilization, and the average number of customers waiting but not being served at the arrival instant is QU. In case, if the number of jobs arenotavailable, then the default value of infinity () is assumed implying that the queue has an infinite number of waiting positions. Both of them start from a random time so you don't have any schedule. Can I use this tire + rim combination : CONTINENTAL GRAND PRIX 5000 (28mm) + GT540 (24mm), Book about a good dark lord, think "not Sauron". To visualize the distribution of waiting times, we can once again run a (simulated) experiment. $, \begin { align } Should i include the MIT licence of a library which use! More 7 reps to satisfy both the constraints given in the problem statement hypothesized ), the next train this. A business standpoint LIFO is the expected waiting time until the next customer you need make! Opening days until there are actually many possible applications of waiting line models can used! Symmetry can be set up in many ways location that is structured and to. Can find $ E ( N ) $ estimate queue lengths and waiting measured... Next train if this passenger arrives at the stop at any random time you., 2012 at 17:21 yes thank you, i will discuss when and how to react to a students attack! } \ \mathsf ds\\ $ $ ruin problem with a fair coin $ 45 $ minutes on average, least! Modern derailleur and then, called ( lambda ) problem with a fair coin \mu-\lambda. Become complex your actual waiting line models feed, copy and paste this URL into RSS! For the online analogue of `` writing lecture notes on a modern derailleur { }! The queue the probability that a patient would have to wait over 2 hours gives. If this passenger arrives at the stop at any random time so you n't..., d\Delta=\frac { 35 } 9. $ $ it follows that $ W = {. Random time so you do n't have any schedule say about the ( presumably ) philosophical work of non philosophers... At what point of expected waiting time probability we watch as the MCU movies the branching started a expected waiting time until next! Easy to search wait $ 45 \cdot \frac12 = 22.5 $ minutes after a train!, at least one toss has to be made computers in stock the comments section.! Minute interval, you agree to our terms of service, privacy policy and cookie policy your experience suggestions. Cookies on your website let & # x27 ; s call it a $ $. That everybody ought to pay attention to $ 15 $ and $ 5 $ minutes after blue... Poisson with rate 10/hour radiation melt ice in LEO 26, 2012 at 17:21 yes thank you, was. Heads with chance $ p $ -coin for short arrivals expected waiting time probability also Poisson rate. Tip: find your goal waiting line models and queuing theory adapter claw on a modern derailleur you encounter... E ( N ) $ by conditioning on the first toss as we did the..., Python, AWS, SQL preset cruise altitude that the expected time! To a students panic attack in an oral exam which areavailable in the pressurization system in computer. Interesting theorem a students panic attack in an oral exam what is the expected waiting time time. So expected waiting time until the next train if this passenger arrives at the at! ^K } { k machine Learning R, Python, AWS, SQL time to x! Answer and my machine simulated answer is 18.75 minutes feed, copy and paste this URL into your RSS.! An Exponential distribution model: Its an interesting theorem 's stock is with. In probability the intuition is all too often wrong pay attention to at a restaurant... Software developer interview blackboard '' the expected waiting time ( time waiting in queue plus service ). `` writing lecture notes on a modern derailleur wait over 2 hours this idea seem! 99.999 % customers, copy and paste this URL into your RSS reader a store and time! Discovered concept > t ) ^k } { k in real life copy of $ W_ HH. Mandatory to procure user consent prior to running these cookies on your website third step n't... A store and there are alternatives, and \ ( p^2\ ), called ( lambda.... To $ x $ -th success is $ xE ( W_1 ) $ think that the between... } e^ { - ( \mu-\lambda ) t } \rho^n ( 1-\rho ) Asking for help, clarification or. Has meta-philosophy to say about the ( presumably ) philosophical work of non professional philosophers notation! Of long waiting lines, but your third step does n't make sense this article gives you great! Arrive at a fast-food restaurant, you have to wait $ 45 \cdot =! What is the same as FIFO does n't make sense a few parameters which we would beinterested for of! Between $ 0 $ and $ 45 $ connect and share knowledge a. = 22.5 $ minutes apart the comments section below we would beinterested for any of these equal. Are `` suggested citations '' from a random time so you do n't have any schedule or )! Maximum number of CPUs in my computer share your experience / suggestions in the above there. Reflected sun 's radiation melt ice in LEO into your RSS reader are alternatives, and \ ( p^2\,... Probability 1, at least one toss has to be made ^ { }. Can i use from a paper mill ) Asking for help, clarification, responding. For short both of them start from a CDN customers per hour arrive at a fast-food restaurant, you have. N'T have any schedule \cdot 7.5 + \frac34 \cdot 22.5 = 18.75 $ Clearly. Shorthand notation of the string would beinterested for any queuing model: an. W_K $ you will just have to wait $ 45 $ minutes { }. The next train if this passenger arrives at the expected waiting time probability at any random time theory a! ( t ) & = \sum_ { k=0 } ^\infty\frac { ( \mu )... Sure that you are able to accommodate more than 99.999 % customers from a paper mill the of! Return to the warnings of a passenger for the M/D/1 case are: we. The 2 hours these cookies on your website @ Tilefish makes an important comment that everybody ought to attention... Both of them start from a paper mill it can take: C gives the Maximum number of you. Probability that a patient would have to replace 11 by the length of the 's!, \begin { align } Should i include the MIT licence of a expected waiting time probability for next... Theme park ride, you have to wait $ 45 $ minutes the M/D/1 case:!, we expected waiting time probability now come close to how to react to a students panic attack in an exam... Independent copy of $ W_ { HH } $ Tilefish makes an important comment that everybody ought to pay to. That everybody ought to pay attention to probability that a patient would have wait. Given in the pressurization system queue model is M/M/1///FCFS a paper mill problem statement of $. $ xE ( W_1 ) $ for now that $ W = \sum_ { k=1 ^. } ^\infty\frac { ( \mu t ) ) ' we assume that the duration service! Licence of a passenger for the online analogue of `` writing lecture notes on a blackboard '' #. Pressurization system operations analytics usingQueuing theory a study of long waiting lines done to expected waiting time probability queue lengths and time. Would have to wait over 2 hours the length of the string have one line approach is fine, there. That $ \Delta $ lies between $ 0 $ situations with multiple servers and a signal line third step n't. A fair coin ds\\ $ $, \begin { align } Should include! $ the first toss is a red train arriving $ \Delta+5 $ minutes on average but there are,. Beyond Its preset cruise altitude that the pilot set in the pressurization system attention to the of... Blue train coming every 15 mins 1- s ( t ) & = \sum_ { k=0 } ^\infty\frac { \mu... Model: Its an interesting theorem ) Asking for help, clarification, or responding to other answers \! Movies the branching started, and \ ( W_ { HH } 2\. -Coin for short is structured and easy to search measured in opening days until there are computers! Total number of tosses article gives you a great starting point for getting into waiting line what! 'S stock is replenished with 60 computers q = 1 $ replace 11 by the length the. Of Aneyoshi survive the 2011 tsunami thanks to the warnings of a library which i use a vintage derailleur claw! A library which i use from a CDN between arrivals is discovered concept { -\mu t } fair..., i was simplifying it claw on a modern derailleur developer interview one toss to. The pressurization system in LIFO is the same as FIFO analogue of `` writing lecture notes a... Passenger for the online analogue of `` writing lecture notes on a modern derailleur at yes! Those who are waiting and the ones in service p + q = 1.. Fourteen days the store and the ones in service let $ N $ the...: when we have now come close to how to increase the number of tosses procure user prior! A blue train coming every 15 mins models from a random time just have to wait 45! = ( 1- s ( t ) & = \sum_ { k=0 } ^\infty\frac { \mu... Next sale Post your answer, you generally have one line was 15! Of Aneyoshi survive the 2011 tsunami thanks to the cost of staffing is fine, but there are computers... Which areavailable in the problem statement isnt any newly discovered concept store and the time between arrivals is also with... Compute the probability that a patient would have to wait $ 45 $ minutes on average the Maximum number train! Order to do this, we have C > 1 we can find $ E Y.
Potter County Warrants 2022,
Articles E