### Program Modelling Concepts

Modelling Processes for Software Analysis before Software Implementation
Data Flow Graph (DFG)
• Data Flow Graph (DFG) as the name says only the data which is flowing in to a process taken into account. for example going to a bank for depositing the cash includes the data 1) input is account number and 2) output data is balance in the account.
• Other examples: Finding the average marks scored by a student: the input data is grades or marks scored and output data is the average grades or marks. the process is the (sum/total number of subjects).
• usually the input data is fed in to a process and output data comes after processing the input data.
• DFG does not have any conditions within it, but has only data entry point and one data output entry point.
• When there is only one set of values of each of the inputs and only one set of values of the outputs for the given input, a DFG is also known to be Acrylic Data Flow Graph (ADFG)
• Example of ADFG: In an FIR Filter with
• y6=a0x6+a1x5+......+a6x0, in this equation for a FIR filter, there are 7 multiplication units , each consumes only one memory to store and has only one value, i.e x0.....x6 has one value and a0, a1....a6 each has one value, so a0x6,.......a6x0 each will also have one value and y6 is also have only one value. So this example comes under ADFG
• But the examples of Non Acrylic DFG includes 1) A status flag setting in a device 2) Input as per output condition of the previous process

### Installing TexLive 2019 in Ubuntu 18.04

Installation of TexLive 2019 in Linux (Ubuntu 18.04 LTS)
TeX (Tech)

Installation of TexLive 2019

Please watch the video for full installation

I used .iso file to download, the Total size is 3.3GB for Linux,

Extract the .iso file to a folder and open a terminal

\$] sudo ./install-tl
(it goes into a terminal mode, which is faster compared to the GUI Mode)

\$] sudo ./install-tl -gui
after the installation, set the PATH, MANPATH and INFOPATH as suggested by LATEX

export PATH=\$PATH:/usr/local/texlive/2019/bin/x86_64-linux
export MANPATH=/usr/local/texlive/2019/texmf-dist/doc/man
export INFOPATH=/usr/local/texlive/2019/texmf-dist/doc/info

put these lines in to the /home/pradeepkumar/.bashrc

We have installed TexLive 2019 and texstudio.

To install texstudio

\$] sudo apt install texstudio
The look and feel of TexStudio looks like this image.

texlive, it install everyt…

### Implementing a new system call in Kernel version 2.6.32

A system call is used by application or user programs to request service from the operating systems. Since the user programs does not have direct access to the kernel whereas the OS has the direct access. OS can access the hardware through system calls only.The following files has to be modified for implementing a system call/usr/src/linux-2.6.32.5/arch/x86/kernel/syscall_table_32.S/usr/src/linux-2.6.32.5/arch/x86/include/asm/unistd_32.h/usr/src/linux-2.6.32.5/include/linux/syscalls.h/usr/src/linux-2.6.32.5/MakefileNew set of files to be createdCreate a new directory newcall/ inside the path “/usr/src/linux-2.6.32.5/” Create new files Makefile, newcall.c and put them in the /usr/src/linux-2.6.32.5/newcall/ folder Create new user files (in any folder of Linux) to test the system call
testnewcall.c, testnewcall.h (created in /home/pradeepkumar) syscall_table_32.S Find the file /usr/src/linux-2.6.32.5/arch/x86/kernel/syscall_table_32.S and add the following line at the end
"…

### Electrical Machine Design (equations)

FactorsDC Machine Transformers Induction Machines Synchronous MachinesOutput EquationPa=CoD2Ln, where Pa=P/h for generators, Pa=P for motorsFor Single Phase
Q=2.22 f Bm Ai Kw Aw d10-3
For Three Phase
Q=3.33 f Bm Ai Kw Aw d 10-3Q=CoD2 L ns
KVA Input Q=
HP * 0.746 / Cos f * hQ=CoD2 L ns
KVA Input Q=
HP * 0.746 / Cos f * h
For Turbo alternators
Q=1.11Bavac KwsVa2 L 10-3/nsOutput CoefficientCo=Bav ac* 10-3where Bav-magnetic loading and ac - electric loadingDNACo=11 Kws Bav ac 10-3Co=11 Kws Bav ac 10-3 Choice of Magnetic LoadingFlux Density in Teeth Frequency of Flux Reversals Size of machineDNAMagnetizing current, Flux Density, Iron lossIron loss, Stability, Voltage Rating, Parallel Operation, Transient ShortCircuit current Choice of Electric LoadingTemperature rise,
speed of machine, Voltage, Armature reaction, CommutationDNAOverload Capacity, Copper losses, Temperature rise, Leakage ReactanceCopper loss, Synchronous reactance, Temperature rise, Stray Load losses,
Voltage rating Flux …