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mean,mode and variance

corelation==>x is independent  y is dependent Regression==>x is dependent y is independent Normal distributions are  symmetric ,  unimodal , and  asymptotic , and the  mean ,  median , and  mode  are all equal. mean(xbar) == avg. of numbers/n; variance(sigma^2)== summation(x-xbar)^2/n; sd(sigma)==sqrt(varinace) Another name for the mean of a probability distribution is expected value Adding a constant to each value in a data set does not change the distance between values so the standard deviation remains the same. Three of the most popular methods of estimation are: The method of moments (MM) The method of maximum likelihood (ML) Bayesian method Regression  is a  data mining  technique used to predict a range of numeric values (also called continuous values),  The histogram for the data:  4; 5; 6; 6; 6; 7; 7; 7; 7; 8  is not symmetric...
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IOT(internet of Things) Notes

<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <script>      (adsbygoogle = window.adsbygoogle || []).push({           google_ad_client: "ca-pub-1673173799321485",           enable_page_level_ads: true      }); </script> Presentation layer defines the format in which the data is to be exchanged between the two communicating entities. • Also handles data compression and data encryption (cryptography).# Basic frequencies you should know####### satellite communication uses ku band for communication its freq. is (12 to 18)GHz ///////4G//////////// Currently in INDIA, 4G LTE band-40 having 2300 to 2400 MHz (TD-LTE) frequency range is active (online) and offered by the operators in indian territory. The other LTE band in 1800 MHz (FDD-LTE) frequency is also auctioned by the INDIA government. But this LTE band is not offered for LTE ...
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JAVA

non-static members which are declared outside of the main which cannot be accessed inside the main function to do that outside members must be declared as static for char i; print(i)--->print nothing in java math.round will round out the float value as 1.2--->2 2.7--->3 toString() method used for to convert Wrapper object to String
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ARM VS AVR

ARM7TDMI:thumb2 instruction set it is 2 bytes  some 4 bytes thumb2 arm+thumb total 37 registers R0-R15 general purpose R13 stack R14 Link(  lr (or r14) is used as a link  register  to  store  the  return address ) by default data abort is handled when an application  read or write an illegal memory location. You can calculate the illegal memory location using by subtracting 8 from the value in R14 (link register). Exceptions  are processed in ARM state The  SWI  instruction causes a  SWI  exception. This means that the processor state changes to  ARM , the processor mode changes to Supervisor, the CPSR is saved to the Supervisor Mode SPSR, and execution branches to the  SWI  vector ARMCM3: two states *debug state *thumb state 16 registers 13 GP 3 special purpose The ARM7TDMI core has a Von Neumann architecture, with a single 32-bit data bus carrying both instructions and data. Th...
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Basic Electronics

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This is a band pass filter In band stop filter C2 is connected in between R1 and C1 (Requires inverting input) Low pass filter High Pass filter (LPF and HPF requires differential input) differentiation and integrator ADDER Subtractor (for integrator, differentiator,adder,subtractor requires inverting input) Diode logic Resistor transistor logic: dissipates more power 1}DCTL(direct coupled transistor logic):it is used for to save space 2}Resistor capacitor transistor logic:input resistor are parallel with capacitors Emitter coupled Logic: it uses NPN transistor in differential amplifier range of input voltages are used so BJT will not goes into saturation region it is due to very high switching speed  also called common mode logic or current switch emmiter follower  CMOS: it utilize power during transition in logic so it uses very less power Power Scale::P=@cv^2.....@ is activity factor CMOS have speed limitation due to in...
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data science questions

Robotics Which of the following is not data type of python a. Dictionary        b. Boolean c. Tuple                d. Integer 2. what is full form of AGV Automated Grouped Vehicles      b. Alternative Guided Vehicles c.Automatic Guided Vehicles          d.All Time Guided Vehicles 3. Which part of the Robot provides motion to the manipulator and end-effectors ? A. Controller                       B. Sensor C. Actuator                           D. None of the above manipulator:it is a    manipulator  is a device used to manipulate materials without direct contact. end-effector: it means last link(or end) of robot generally in serial manipulating robots  Actuator:  an  actuator  is an electrom...
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RTOS(Real Time Operating System) notes

RTOS NOTES Hard realtime OS has less jitter and Soft real time jitter has High jitter  jitter : it is the time between two interrupt Event driven systems switch between tasks based on their priorities while time sharing systems switch the task based on clock interrupts. Most RTOS’s use a pre-emptive scheduling algorithm. The most common designs are Event-driven –  switches tasks  only when an event of higher priority needs servicing; called  preemptive priority , or priority scheduling. Time-sharing – switches tasks on a regular clocked interrupt, and on events; called  round robin . A task has three stages 1. Runing 2.Ready 3.Blocked(Waiting for an event,I/O for example) On simpler non-preemptive but still multitasking systems, a task has to give up its time on the CPU to other tasks, which can cause the ready queue to have a greater number of overall tasks in the ready to be executed state ( resource starvation ). laxity = Absolute deadline...
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