MANAGEMENT INFORMATION SYSTEMS

MIS – adalah satu dari banyak mata kuliah yang diberikan kepada mahasiswa TeknikIndustri, Universitas Indonesia
Sesuai namanya, MIS adalah bagaimana mengelola suatu informasi dalam suatu sistem yang dapat memberikan manfaat yang sangat penting didalam bisnis.
Bicara MIS, maka tidak dapat dilepaskan dari yang namanya Computer (hardware&software)
Sejak tahun 1950-an, terjadi perkembangan yang sangat dramatis didalam penggunaaan Hardware dan software komputer baik secara individu maupun perusahaan.
Berikut adalah model umum MIS dalam suatu perusahaan

McLeod, page 26

REVIEW MATA KULIAH

KNOWLEDGE MANAGEMENT :
Adalah sistem informasi yang dirancang untuk memfasilitasi, mengenali, mengumpulkan, meng-integrasikan dan menyebarkan knowledge dalam organisasi.
KM systems fokus dalam membuat, mengumpulkan, mengelola dan menyebarkan knowledge daripada data dan informasi
Davenport and Prusak (1998) states 8 principles of knowledge management. They summarize. what is known and are worth repeating here.
1. Knowledge originates and resides in people’s heads
2. Knowledge sharing requires trust.
3. Technology enables new knowledge behaviors
4. Knowledge sharing must be encouraged and rewarded
5. Management support and resources are essential
6. Knowledge initiatives should begin with a pilot program
7. Quantitative and qualitative measurements are needed to evaluate the initiative
8. Knowledge is creative and should be encouraged to develop in unexpected ways.

E-COMMERCE
Electronic Commerce- Penggunaan Komputer dan jaringan di dalam bisnis, dengan kata lain Jual beli produk menggunakan internet.
Ada dua jenis e-commerce, yaitu:
· Business to Cunsumer (B2C) - transaksi yg terjadi antara pebisnis dan konsumenya
· Business to Business (B2B) – transaksi yg terjadi antara dua pebisnis

BARCODE
Barcode adalah salah satu metode didalam pengumpulan dan identifikasi data secara otomatis Ditemukan dan dipatenkan senilai 2.612.994 USD pada Oktober 1952 oleh Joseph Woodland dan Bernard Silver
DEFINISI – Suatu gambar kecil yang memuat garis dan spasi sebagai kartu identitas untuk mengidentifikasi suatu produk tertentu, orang dan lokasi. Kode yang memperlihatkan batang/garis vertikal dan spasi yg mewakili simbol dan nomor tertentu
Barcode biasanya terdiri dari 5 bagian, yaitu:
1. Quite zone
2. Start character
3. Data characters
4. Stop characters
5. Another quite zone
tapi bagaimana barcode bekerja??

Scanner membaca Bar dan spasi yang ada di label. Angka hanya untuk manusia. Informasi dari scanner ditransfer ke komputer yang sudah terkodifikasi dan memuat data harga, sisa barang yg tersedia dan data lainnya

Manfaat Barcode??
Bagi Perusahaan• menunjukkan harga yang akurat,
• memperkecil kesalahan penghitungan oleh manusia, mengetahui dengan tepat persediaan barang yg ada (inventory control)
Bagi Pelanggan
• mendapatkan barang yang dicari / tidak kehabisan barang yang dicari
karena sistem akan segera memesan barang yang kehabisan stock.
• Terhindar dari kerugian, karena kemungkinan error
atau salah memasukkan jumlah uang yang harus dibayar

SYSTEM ANALYST
Suatu pekerjaan yang sangat berkaitan dengan penggunaan komputer (hardware&software). Memberikan solusi IT terhadap efisiensi dan produktifitas perusahaan
How do they Work??
BUSINESS PROCESS
Business process atau metode bisnis adalah kumpulan dari tugas-tugas yang terkait, yang digunakan untuk memecahkan permasalahan-permasalahan yang ada

Business Process haruslah:
1. Mempunyai target
2. Mempunyai input yg jelas
3. Mempunyai output yg jelas
4. Ada sumber daya
5. Ada beberapa aktifitas
6. Bisa saja melibatkan lebih dari satu unit kerja
7. Menciptakan nilai bagi customer baik internal maupun external

Coding for distributions (geometric/weibull)

#include
#include
#include

long fact(int n)
{
if(n<=0)
return 1;
else
return n*fact(n-1);
}


double geomean(int x,double p,double q)
{
if(x>0)
return pow(q,x-1)*p;
else
return 0;
}


double weibpdf(int x, double v, double a, double b)
{
if(x return 0;
else
{
return b/a*(pow((x-v)/a,b-1))*exp(-pow((x-v)/a,b));
}
}


double weibcdf(int x, double v, double a, double b)
{
if(x return 0;
else
{
return (1 - exp(-pow((x-v)/a,b)));
}
}

double poisson(int x, double a)
{
if(x<0)
return 0;
else
{
return (exp(-a)*pow(a,x))/fact(x) ;
}
}


double binom(int x,double p,double q,int n)
{
if(x>=0)
return fact(n)/(fact(x)*fact(n-x))*pow(p,x)*pow(q,n-x);
else
return 0;
}


int main()
{
int ch;
double p,q,v,a,b;
int x,n;
clrscr();


do
{
printf("\nExit.");
printf("\nGeometric Mean.");
printf("\nWeibull Distribution.");
printf("\nPoisson Distribution.");
printf("\nBinomial Distribution.");
printf("\nEnter your choice => ");
scanf("%d",&ch);
if(ch==1)
{
printf("\n\tEnter the value of x,p,q => ");
scanf("%d%lf%lf",&x,&p,&q);
printf("\n\tGeometric Mean = %lf",geomean(x,p,q));
}
else if(ch==2)
{
printf("\n\tEnter the value of x,v,a,b => ");
scanf("%d%lf%lf%lf",&x,&v,&a,&b);
printf("\n\tWeibull pdf, f(%d) = %lf",x,weibpdf(x,v,a,b));
printf("\n\n\tWeibull cdf, F(%d) = %lf",x,weibcdf(x,v,a,b));
}

else if(ch==3)
{
printf("\n\tEnter the value of x,a => ");
scanf("%d%lf",&x,&a);
printf("\n\tPoisson Distribution, p(%d) = %lf",x,poisson(x,a));

}
else if(ch==4)
{
printf("\n\tEnter the value of x,p,q,n => ");
scanf("%d%lf%lf%d",&x,&p,&q,&n);
printf("\n\tBinomial Distribution, p(%d) = %lf",x,binom(x,p,q,n));
}
}while(ch!=0);
getch();
return 0;
}


Astha
MCA 4510/09

Coding for M/M/1 server

#include
#include
void main()
{
int i,a,d,arrival[11],clock=0,inter[]={2,3,1,4,1,6,1,1,5,2,1},service[]= {2,5,4,3,3,5,6,6,6,3,2};
int wait[11],q=0,sum=0,avg,server;
arrival[0]=clock+inter[0];
d=clock+service[0];
server=1;
a=arrival[0];
wait[0]=0;
for(i=0;i<11;i++){arrival[i]=arrival[i-1]+inter[i];}printf("clock=%d (A=%d)(D=%d)(W=%d)",clock,a,d,wait[0]) ;i=1;while(clock<30){if(ad)
{wait[i]=0;
printf("clock=%d (A=%d)(D=%d)(W=%d)",clock,a,d,wait[1]) ;
i++;
}
else
if(da)
{
wait[i]=d-a;
}
printf("\nclock = %d (A,%d) (D,%d) (w,%d)",clock,a,d,wait[i]);
}
else
{
wait[i]=0;
printf("clock=%d (A=%d)(D=%d)(W=%d)",clock,a,d,wait[i]) ;
server=0;
}
}
else
{
clock=0;
a=arrival[i];
d=clock+service[i-q];
if(a{
wait[i]=d-a;
}
else
{
wait[i]=0;
i++;
printf("clock=%d (A=%d)(D=%d)(W=%d)",clock,a,d,wait[i]) ;
}
}
else
{
clock=0;
a=arrival[i];
d=clock+service[i];
wait[i]=d-a;
i++;
printf("clock=%d (A=%d)(D=%d)(W=%d)",clock,a,d,wait[i]) ;
for(i=0;i<11;i++)
{
sum+=wait[i];
}
avg=sum/11;
if (avg<1)
printf("efficient system");
else
printf("inefficient system");
getch();
}



neha bahadur
mca455309

Simulation & Modeling (ASSIGNMENTS) [LAB + Theory}

Roll No.	Assignments
2032,4501	Music Shop Inventory Problem,Simulation of computer system
4502,4506	Web Simulation,
4507,4568,4538	Food bazaar, Simulation of Queuing System and its applications e.g. Food Bazaar
4508,4536,4546
Simulating a banquet hall,Input Output modeling for simulation
4509
Random Number generation for simulation
4510,4525,4520	Telephone Simulation System, Application of Simulation for solving network flow problems
4511,4543	Simulating Car Parking
4513,4533,4531	Monte-carlo Simulation
4514	Simulating grocery Shop
4516,4535,4551/08	Traffic Simulation, Simulation of websites to improve traffic for a website
4515,4528,4529	Understanding GPSS
4518,4554,4566	Gaming Simulation
4519,4524	Conducing web simulation on e-commerce portals
4530,4551,4556	Simulating Delhi Metro, Understanding Object oriented simulation
4534,4557	Learning to solve Problems using simulation
4539,4542	Developing a Simulation Database: Studying case studies/FAQs
4540,4547,4543	Online Traffic Monitoring system
4541,4545,4555	Developing a Simulator for keyword analysis,Application of Simulation for Forecasting
4537,4532,4521	Random Number Generation in C++,Studying Simulation languages like SIMSCRIPT,GPSS,MODSIM
4550,4563	Solving problems for input modeling [17,18,20,21]
4523,4552	Study applications of random generators in simulation and other fields illustrating by solving problems [2,9,10,15]
4545660,4562	Application of Simulation for security and anti-spamming
4522,4526	Understanding DEVS
44532,4533,4568	Using general purpose simulation language for problem solving [pg 119 1,2,3,4,5)
4535,4538,4541	Developing simulation program in C [pros & cons] [Pg. 119 7,8,9,10]
4544,4548	Output Analysis for a single model
4549,4552	Comparison & Evaluation of Alternative system designs
4553,4558	Simulation of computer networks

Simulation & Modeling Software

We can understand computer simulation language as the language which describes operation of a simulation on a computer.

It can be broadly categorized in following two categories:

1. continuous
2. Discrete event

Many lnguages have a graphical interface and are capable of performing simple statistical analysis of the results.


While using discrete-event languages we can easily generate pseudo-random numbers and determine variables using different probability distributions.


Some of the Discrete event and continuous language packages have been listed below:


AutoMod
eM-Plant
Arena
ExtendSim simulation environment for discrete event, continuous, discrete-rate and agent-based simulation.[1]
GASP
GPSS
Plant Simulation
Simio software for discrete event, continuous, and agent-based simulation.[2]
SimPLE++
SimPy, an open-source package based on Python
SIMSCRIPT II.5, a well established commercial compiler
Simula
Java Modelling Tools, an open-source package with graphical user-interface[3]
Poses++, a discrete-event simulation system with Petri net based modeling
OMNeT++, a C++-based discrete-event simulation package.
Mirelle, a programming/scripting language with simulation support. [4]


Some of the Continuous simulation languages package are:

1. 
   Advanced Continuous Simulation Language (ACSL), which supports textual or graphical model specification
   
2. Diesel Model Description Language
   
3. DYNAMO
   
4. SimApp, simple simulation of dynamic systems and control systems [6]
   
5. Simgua, simulation toolbox and environment, supports Visual Basic [7]
   
6. Simulation Language for Alternative Modeling (SLAM) (There used also be a Simulation Language for Analogue Modeling (SLAM))
   
7. VisSim, a visually programmed block diagram language
   Hybrid, and other.
   
8. LMS Imagine.Lab AMESim[8], simulation platform to model and analyze multi-domain systems and predict their performances
   
9. Flowmaster V7[9] Software for the analysis of fluid mechanics within pipe networks using 1D Computational Fluid Dynamics
   
10. AnyLogic multi-method simulation tool, which supports System dynamics, Discrete event simulation, Agent-based modeling
    
11. Modelica: open-standard object-oriented language for modeling of complex physical systems
    Simulink: Continuous and discrete event capability
    
12. Scicos: Continuous-time, discrete-time and event based simulation tool distributed with ScicosLab: It contains a block diagram editor, a compiler, simulator and code generation facilities: Free software.
    
13. XMLlab: simulations with XML
    
14. Flexsim:3D process simulation software for continuous, discrete event, or agent-based systems.
    
15. Simio software for discrete event, continuous, and agent-based simulation.
    
16. EICASLAB:Continuous, discrete and discrete event capability specifically devoted to support the automatic control design.
    
    

Source:http://en.wikipedia.org/wiki/Simulation_language

Simulation Software

Discuss the following periods in simulation history?


a. The period of Search: Simulation was conducted in FORTRAN and other gernal purpose languages. No specific simulation specific routines. Much effort was on expanding searcn for unifying concepts and the development of reusable routines to facilitate simulation(1955-60)

b Advent : It is the period of forerunners of SPL we use today(1961-65)

GPSS developd by Geoffery Gordon at IBM and appeared in 1961. General Purpose Simulation system was developed for quick simulation of communication and computer system. It is a block disgram based representation (similar to process flow diagram) and suited for queuing models.


Phillip J Kiviat developed GASP (General Activity based simulation program). Originally it was based on GPL ALGOL but later based on FORTRAN.

other SPL developed are SIhMULA(extension of ALGOL)

c. The Formative period (from 1966-1970)

Concepts were reviewed adn refined to promote more consistent representation of each language 's world view.

SIMSCRIPT II represents major advancement in SPLs. In its free form english like language.


d. The Expansion period (from 1971-1978)

Improvement in GPSS. Inclusion of interactive debugger. Efforts made to simplify modeling process. Using simula an attempt was made to develop system definition from high level user perspective that could be translated automatically in an executable format.

e. Consolidation and Regeneration

This period from 1979 GASP appeared SLAM II and SIMAN

SLAM II(Simulation language for alternative modeling) produced by Prisker and Associates.

for providing multiple modeling perspectives and combined modeling capabilities. Event scheduling persective and a noetwork world view and continuous component.

f. Integrated Environment

Availability of SPL for personal computers, GUI ,animation and other visulaization tools,input/output analyzers. use of process flow or block diagram and reducing need to remeber syntax. Availability of 2 D /3D scale drawings





SIMAN

Linear Congruential method ( Random Number generation )

#include
#include
#define true 1
#define false 0
void main()
{
int x[30];
int flag=true,i,a,c,m,x0;
float r[30];
printf("\n Enter a,c,m,x0");
scanf("%d%d%d%d",&a,&c,&m,&x0);
x[0]=x0;
i=1;
while(flag==true)
{
x[i]=(a*x[i-1]+c)%m;
r[i]=x[i]/(float)m;
if(x[i]==x[0])//Now onwards series will repeat
flag=false;
i++;
printf("x[i]=%d\n",x[i-1]);
}
getch();
}




omprakash sharma

4552/09

Weibull Distribution Implementation (Simulation and Modeling)

#include
#include
#include

double f(int x, double v, double a, double b)
{


if(x< v)
return 0;

else
{
return b/a*(pow((x-v)/a,b-1))*exp(-pow((x-v)/a,b));

}

}

double F(int x, double v, double a, double b)
{
if(xreturn 0;

else
{

return (1 - exp(-pow((x-v)/a,b)));

}



}


int main()
{

int x;
double v,a,b;
clrscr();



printf("enter d value of x, location, shape & scale: ");
scanf(" %d %lf %lf %lf",&x, &v, &b, &a);

printf(" f(%d) = %f",x,f(x,v,a,b));

printf(" F(%d) = %f",x,F(x,v,a,b));

getch();
return 0;
}


Pankaj kumar
mca4506/09

Future Event LIST (Simulation & Modeling)

BY NEHA BAHADUR MCA/4553/09

#include
#include
#include

int inter[9] = {1,1,6,3,7,5,2,4,1};
int service[9] = {4,2,5,4,1,5,4,1,4};
int i=0,j=0;

struct eventinfo
{
int type;
int time;
struct eventinfo *next;
} * header;


void addevent(int time, int type)
{
struct eventinfo * node = (struct eventinfo *)malloc(sizeof(struct eventinfo));
struct eventinfo *p, *q;
node->type = type;
node -> time = time;

if(header->next == NULL)
{
header ->next = node;
node->next = NULL;
return ;
}
p = header->next;
q = header;
while((p->timenext;
}
q->next = node;
node -> next = p;

}
void print()
{
struct eventinfo * p = header->next;
while(p!=NULL)
{
//printf("\n");
if(p->type ==1)
printf("(A,");
else
printf("(D,");
printf("%d)",p->time);
p =p->next;


}
}
void depart()
{
int nexttm;
struct eventinfo * node = header->next;
header -> next = node->next;
nexttm = node->time+service[j++];
header->type = 1;
if(header->next != NULL && i>=j)
addevent(nexttm,0);
else
{
header->type =0;
j--;
}
//else server is idle
printf("departure ");
print();

}
void arrival()
{
struct eventinfo *node;
int nexttm;
node = header->next;
header->next = node ->next;
nexttm = node->time + inter[i++];
addevent(nexttm,1);
if(header->type == 0)
{
nexttm = node->time + service[j++];
//printf(" next depart = %d service = %d",nexttm, j-1);
addevent(nexttm,0);
header->type = 1;
}
printf("arrival ");
print();
}
void main()
{

int t, eventtime;

clrscr();
header = (struct eventinfo *) malloc(sizeof(struct eventinfo));
header ->time=0;
header->next = NULL;
header->type = 0;


t =0;
addevent(0,1);
eventtime = header->next->time;
while(t<=60){if(t == eventtime){printf("\n t = %d\t",t);if(header->next->type ==1)
arrival();
else
depart();
if(header->next != NULL)
eventtime = header->next->time;
else
eventtime = 100;
if(i>=9 || j>=9)
eventtime = 100;
}
t++;
if(t>eventtime)
t = eventtime;
}

getch();
}

Future Event LIST (Simulation & Modeling) (Linked list Implementation)

by Himanshu Singla

#include
#include
#include

int inter[9] = {1,1,6,3,7,5,2,4,1};
int service[9] = {4,2,5,4,1,5,4,1,4};
int i=0,j=0;

struct eventinfo
{
int type;
int time;
struct eventinfo *next;
} * header;


void addevent(int time, int type)
{
struct eventinfo * node = (struct eventinfo *)malloc(sizeof(struct eventinfo));
struct eventinfo *p, *q;
node->type = type;
node -> time = time;

if(header->next == NULL)
{
header ->next = node;
node->next = NULL;
return ;
}
p = header->next;
q = header;
while((p->timenext;
}
q->next = node;
node -> next = p;

}
void print()
{
struct eventinfo * p = header->next;
while(p!=NULL)
{
//printf("\n");
if(p->type ==1)
printf("(A,");
else
printf("(D,");
printf("%d)",p->time);
p =p->next;


}
}
void depart()
{
int nexttm;
struct eventinfo * node = header->next;
header -> next = node->next;
nexttm = node->time+service[j++];
header->type = 1;
if(header->next != NULL && i>=j)
addevent(nexttm,0);
else
{
header->type =0;
j--;
}
//else server is idle
printf("departure ");
print();

}
void arrival()
{
struct eventinfo *node;
int nexttm;
node = header->next;
header->next = node ->next;
nexttm = node->time + inter[i++];
addevent(nexttm,1);
if(header->type == 0)
{
nexttm = node->time + service[j++];
//printf(" next depart = %d service = %d",nexttm, j-1);
addevent(nexttm,0);
header->type = 1;
}
printf("arrival ");
print();
}
void main()
{

int t, eventtime;

clrscr();
header = (struct eventinfo *) malloc(sizeof(struct eventinfo));
header ->time=0;
header->next = NULL;
header->type = 0;


t =0;
addevent(0,1);
eventtime = header->next->time;
while(t<=60){if(t == eventtime){printf("\n t = %d\t",t);if(header->next->type ==1)
arrival();
else
depart();
if(header->next != NULL)
eventtime = header->next->time;
else
eventtime = 100;
if(i>=9 || j>=9)
eventtime = 100;
}
t++;
if(t>eventtime)
t = eventtime;
}

getch();
}

Application of Weibull Distribution

#include
#include
#include

double f(int x, double v, double a, double b)
{


if(x< v)
return 0;

else
{
return b/a*(pow((x-v)/a,b-1))*exp(-pow((x-v)/a,b));

}

}

double F(int x, double v, double a, double b)
{
if(xreturn 0;

else
{

return (1 - exp(-pow((x-v)/a,b)));

}



}


int main()
{

int x;
double v,a,b;
clrscr();



printf("enter d value of x, location, shape & scale: ");
scanf(" %d %lf %lf %lf",&x, &v, &b, &a);

printf(" f(%d) = %f",x,f(x,v,a,b));

printf(" F(%d) = %f",x,F(x,v,a,b));

getch();
return 0;
}

Application of Poisson Distribution

#include
#include
#include

long fact(int n)
{

if(n<=0)
return 1;

else
return n*fact(n-1);

}

double poisson(int x, double a)
{

if(x<0)
return 0;

else
{
return (exp(-a)*pow(a,x))/fact(x) ;
}
}

int main()
{

int x;
double mean;
clrscr();



printf("enter d value of x & mean: ");
scanf(" %d %lf",&x, &mean);

printf(" p(%d) = %f",x,poisson(x,mean));

getch();
return 0;
}



by Amrender

Triangular Distribution

#include
#include
#include

double f(double x, double a, double b, double c)
{


if(a <= x && x <= b)
{

return (2*(x-a))/((b-a)*(c-a));
}
else if( b < x && x <= c)
{
return 2*(c-x)/((c-b)*(c-a));
}
else
return 0;

}

double F(double x, double a, double b, double c)
{
if(x<=a)
return 0;

else if( a{

return ( (x-a)*(x-a)/((b-a)*(c-a)) );

}
else if(b < x && x <= c )
{

return (1 - (c-x)*(c-x)/((c-b)*(c-a)));

}
else if(x>c)
return 1;
}


int main()
{

double x,a,b,c;
clrscr();



printf("enter d value of x, a, b & : ");
scanf(" %lf %lf %lf %lf",&x, &a, &b, &c);

printf(" f(%.2f) = %f",x,f(x,a,b,c));

printf(" F(%.2f) = %f",x,F(x,a,b,c));

getch();
return 0;
}

)
By Alka (4501/09)

Linear Congruential method ( Random Number generation )

#include
#include
#include
int main()
{
int a,c,x0,m,n1,n2,true;

clrscr();
printf(" enter a, c, x0, m : ");
scanf(" %d %d %d %d", &a, &c, &x0, &m);



n1 = x0;

while(true !=1)
{


n2 = (a*n1+c) % m;

printf(" %.2f\t",(float)n1/m );

if(n2 == x0)
true = 1;

n1 = n2;


}

getch();
return 0;
}

by Amrendra Kumar mca/4549/09

Future Event LIST (Simulation & Modeling)

Script for grocery shop with given inter-arrival/service time distribution assumed

by Amrendra Kumar mca/4549/09


#include
#include
#include
void addevent(int,int);
void depart();
void arrival();


struct eventinfo
{
int type;
int time;
struct eventinfo *next;
} * header;
int inter[9] = {1,1,6,3,7,5,2,4,1};
int service[9] = {4,2,5,4,1,5,4,1,4};
int i=0,j=0;

void main()
{
int t, eventtime;
clrscr();
header = (struct eventinfo *) malloc(sizeof(struct eventinfo));
header ->time=0;
header->next = NULL;
header->type = 0;
t =0;
addevent(0,1);
eventtime = header->next->time;
while(t<=60){if(t == eventtime){printf("\nt=%d ",t);if(header->next->type ==1)
arrival();
else
depart();
if(header->next != NULL)
eventtime = header->next->time;
else
eventtime = 100;
if(i>=9 || j>=9)
eventtime = 100;
}
t++;
if(t>eventtime)
t = eventtime;
}

getch();
}

void addevent(int time, int type)
{
struct eventinfo * node = (struct eventinfo *)malloc(sizeof(struct eventinfo));
struct eventinfo *p, *q;
node->type = type;
node -> time = time;
if(header->next == NULL)
{
header ->next = node;
node->next = NULL;
return ;
}
p = header->next;
q = header;
while((p->timenext;
}
q->next = node;
node -> next = p;

}
void print()
{
struct eventinfo * p = header->next;
while(p!=NULL)
{
//printf("\n");
if(p->type ==1)
printf("(A,");
else
printf("(D,");
printf("%d)",p->time);
p =p->next;


}
}
void depart()
{
int nexttm;
struct eventinfo * node = header->next;
header -> next = node->next;
nexttm = node->time+service[j++];
header->type = 1;
if(header->next != NULL && i>=j)
addevent(nexttm,0);
else
{
header->type =0;
j--;
}
print();

}
void arrival()
{
struct eventinfo *node;
int nexttm;
node = header->next;
header->next = node ->next;
nexttm = node->time + inter[i++];
addevent(nexttm,1);
if(header->type == 0)
{
nexttm = node->time + service[j++];
addevent(nexttm,0);
header->type = 1;
}
print();
}

Measures of Central tendency

According to Prof Bowley averages are statistical constants which provide an idea about the concentration of values in the central part of the distribution. The five common measures of central tendency are :

1. Mean [Airthmetic mean]
2. Median
3. Mode
4. harmonic mean
5. Geometric mean

According to Prof. Yule following are the characterstics required to measure central tendency:

1. Central tendency should be rigidly defined
2. It should be comprehensive and easy to determine
3. Should be based on all observations
4. It should not be much affected by the fluctuation of sampling
5. It should not be affected by extreme values


Let us talk about these distributions in detail:

1. Arithmetic mean: Arithmetic mean of a set of observations can be calculated as their sum divided by the number of observations

In case f_i is the frequency of variable x_i then

distribution becomes

'

Properties of Arithmetic Mean

1. Algebric sum of deviations of a set of values from their arithmetic mean is zero
2. The sum of squares of the deviation of a set of values is minimum when it is taken about mean


Applications of Mean


Arithmetic means have many merits. it is rigidly defined,easy to understand and calculate,based upon all observations. It is open to mathematical treatment. Further among all the available averages it is least affected by fluctuation in sampling. That is why it is also called a stable average.

However it has some demerits. It cannot be determined just by inspection. Neither we can locate it graphically. Arithmetic mean cannot be used in case we are dealing with qualitative data. In case we have data dealing with intelligence,happiness, honesty we cannot use mean to measure center of tendency. Further we cannot use arithmetic mean even if single observation from data is missing or lost or wrong. Another demerits is that arithmetic mean is highly affected by the extreme values in case there are extreme values it will give distorted picture of distribution and may not represent the distributions. Arithmetic mean may lead to wrong conclusions even if details of data from which it is computed is not given. Just check out the following example:

Let exam marks for 2 students be as follows


Shyam

name	year 1	year 2	year 3
Rama	50	60	70
70	60	50

In both case of Rama and Shyam average marks(arithmetic mean) are 60 however from data we can analyze Rama is improving and Shyam is decreasing.

In case we have extremely asymmetrical (skewed distributions arithmetic mean cannot be suitable measure of location.

simulation question bank

1. What is simulation? List a few advantages and disadvantages of simulation.
   
2. Differentiate between the following:
   
   1. Continuous and Discrete Systems
      
   2. Static and Dynamic Systems
      
   3. Open and Closed Systems
      
   4. Deterministic and Stochastic activities
      
   5. Static Physical Models and Dynamic Physical Models
      
   6. Static Mathematical Models and Dynamic Mathematical Models
      
3. Write short notes on
   
   1. Monte –Carlo methods
      
   2. M/M/1 model
      
   3. Continuous probabilistic distributions
      
   4. Binomial Distribution
      
   5. Bernoulli Distribution
      
   6. Exponential Distribution
      
   7. Poisson Distribution
      
   8. Erlang Distribution
      
   9. Log normal distribution
      
   10. Geometric distribution
       
   11. Hyper geometric distribution
       
   12. Normal distribution
       
4. What is Discrete system simulation?
   
5. Write short notes on GPSS. Explain at least 5 GPSS block-diagram symbols.
   
6. What do you mean by Action Times and Succession of Events.
   
7. Design a supermarket simulation model using GPSS symbols.
   
8. Design a Telephone System simulation model using GPSS symbols.
   
9. Write the different techniques of simulation output analysis.
   
10. What are the different methods to generate random number?
    
11. What are the different tests to test for random numbers?
    
12. Discuss the applications of Weibull distrbution real life in detail?
    
13. What do you mean by replication of runs? What is batch means ?
    
14. What is project management?
    
15. What is queuing model? How it is useful for Simulation? Explain all different
    kind of Queuing Model in detail
    
    

Key E-commerce Terms

• E-Commerce : electronic commerce was meant for facilitation of commercial transactions electronically, using technology such as Electronic Data Interchange (EDI), Electronic Funds Transfer (EFT), etc

• Models of e-commerce : B2B,B2C, C2B AND C2B

• EDI: can be stated as collection of standard message formats to exchange data between organizations computers via any electronic service.

• SET: is a standard protocol for securing credit card transactions over insecure networks, more specifically addressing transactions over Internet. Please note clearly, SET is not itself a payment system, but rather a set of security protocols

• Merchant account: When you want to have credit card, you fill up form/details and submit same to financial institution, on similar lines when some want to start e-business/ online transactions (which need online transaction through credit, debit, charge cards), one must step up a merchant account.

Web Site testing and maintenance issues

In technical jargons testing is also popularly known as “AT”, i.e. acceptance testing.
Success of your website depends on this factor in major way. You should do self (means self) check in order to cross validate, that all things are working properly, for e.g.

- Forms filled by users is properly stored in database
- Hyperlinks / associate links to work properly
- Security related stuff, encryption/ SSL etc totally secure!
- Make a accentuate test, to check who much load website can carry

Maintenance is ongoing endeavor, which will go long way. After website is through with testing and becomes online, it becomes your moral responsibility to nurture this “new kid on the block”. One has to constantly monitor traffic and evaluate web site activities. Remember most of knowledgeable visitors, check first thing while visiting website is “when it was last updated”, it gives impression that how serious/updated seller is about business ! Also, it’s extremely vital to be innovative form time to time, static websites doesn’t last long, one has to lead with latest web technologies available and always dig out room for improvements.

When traffic grows, one has to careful do bandwidth/space calculations/server processing speeds which host websites/ dns entries, etc, slow opening websites gives bad impression and you might loose potential customers. Keep visitor count tab on website, in order to track things in professional way.

Last but not least, “value visitor feedback”, which can really make wonders for you.

Building E-commerce website

Why you want to build e-commerce site

Not only with e-commerce website, but one should always ask himself/herself during start of new project/process/business, why we are doing this adventure. As everything in today’s fast moving world is linked to TEM (time/energy/money), one should take every step to avoid landing into pitfall!

Now let’s spend a minute focusing on e-commerce stuff. Before jumping into, this new adventure, its good to have quick look on following FAQ

i) What’s wish list on products/services?
ii) Should allow customers to order products/services on the fly
iii) Technical support for products/services
iv) How will be advertise our products/services and website itself?
v) Collect information about current and potential customers
vi) Skilled/ technical Manpower requirement for running show
vii) Build e-business image and brand
viii) Also showcase links to related websites
ix) Capex and opex calculations ?


What will be website/portal structure?

Need of hour in today’s fast moving era, “how fast and accurate you are able to provide information to customers”; …one has to believe this after google grand success!

Similarly for e-commerce website, we must organize the information/content very carefully and how fast/quickly you are able to provide info to info seekers / potential customers. Some of noteworthy things to mull upon:

i) Name of new baby, i.e. e-commerce’s name
ii) Your identify marks, logo/trademarks
iii) Database for capturing customer information
iv) Search option, to dig out info quickly
v) Vision and Mission Statement
vi) Contact us
vii) Site Map
viii) Copyright info
ix) No of visitors of day
x) Forms for registration process
xi) Press release and testimonies
xii) Offers on the shelf
xiii) Careers
xiv) Links to associate websites
xv) Domain name registration and web space

Apart from aforesaid stuff, one must follow 2 simple principles a) your website should provide what is speaks for b) Keep it as simple as possible! Multiple layers of associated web links/pages make things complicated, which could eventually frustrate customers.
Also creating logically like with flow-chart in hand to set navigation would be really helpful. Registration forms should be kept very handy and ask to the point information.

Techniques to be used

Basic Techniques:
- Maintain consistency in flow
- Internal hyperlink to connect different pages
- Navigation bar for quick search
- Using Splash pages – Some websites needs showy entrance, with animations and sound effects to highlight effects
- Text and icon hyperlinks can be positioned in body of a webpage to help viewers navigate a website
- Using color, its critical as it should showcase theme and concept
- Font to be carefully as Arial for headings, time roman for text, etc
- Background images, small images are preferred then large ones
- Adding thumbnail is also trendy concept these days
- Frames and form to be kept simple, with to the point questions


Web Development tools

As we all know web development has been one of the fastest growing industries,courtesy popularity of Internet cloud. By 1995 there were fewer than 1,000 web development companies in the US and by 2005 there were over 30,000 such companies (officially registered). It has been observed that the web development industry is expected to grow over 20% by 2010. The growth of this industry is linked with e-commerce, as it opens global market to push selling products /services. Further, cost of Web site development and hosting has dropped dramatically. This has become possible mainly due to too many players joining the boat.

Speaking about, web development tools and platforms there are many options available on the plate. Many are even available to the public free of charge to aid in development. LAMP (Linux, Apache, MySQL, PHP) is a popular example of web development software which is usually distributed free of charge. Availability of freely available tools and software have manifested into many people around the globe. New Web sites are being launched daily and this ha contributing to increase in s no doubt contributed to the web development popularity.

Web Development can be further split into many areas. Basic web development hierarchy includes Client side and Server side coding.Client Side Coding includes scripting languages,web designing software and more:

• HTML/XHTML/XML for presenting content in a webpage.
• Scripting Languages like JavaScript/Jscript/Vb Script and more for adding little interactivity
in HTML webpages.
• New technologies like AJAX which provide facilities for adding user friendly options on the
webpage. It is becoming popular as it improves the user experience with the website.
• Macro Media Dream weaver and any more software available to easily code website.
• Microsoft Silverlight Microsoft's browser plug-in are now available that enables animation,
vector graphics and high-definition video playback and more.


Server Side Coding can be done using following technologies:


• ASP (Active Server Pages)
• Cold Fusion is an application server and software language used for creating dynamic websites.
• CGI and/or Perl: Common Gateway Interface (CGI) provide dynamic WebPages to their users and provides interaction between client and server. Perl programming language is simple, provides solid features for powerful string manipulation, can be easily integrated with C and C++.
• Java, e.g. J2EE or WebObjects:Provides strong features for web server programming.
• Lotus Domino: It s an IBM server . It provides enterprise-grade e-mail, collaboration capabilities and custom application platform.
• PHP: It is a open source programming language which is easy to use
• Smalltalk e.g. Seaside, AIDA/Web: It is an object-oriented, dynamically typed, reflective programming language.
• SSJS e.g. Aptana Jaxer, Mozilla Rhino: Server-side JavaScript (SSJS) refers to JavaScript that runs on server-side.
• Websphere : Integration and application infrastructure software (IBM product)
• .NET Technologies(Microsoft proprietary):Provide features to develop user friendly dynamic page.
Implementing an E-commerce Site

Let's say that you would like to create an e-commerce site. There are three general ways to implement the site with all sorts of variations in between. The three general ways are:
• Enterprise computing
• Virtual hosting services
• Simplified e-commerce
These are in order of decreasing flexibility and increasing simplicity.
Enterprise computing means that you purchase hardware and software and hire a staff of developers to create your e-commerce web site. Amazon, Dell and all of the other big players participate in e-commerce at the enterprise level. You might need to consider enterprise computing solutions if:
• You have immensely high traffic - millions of visitors per month
• You have a large database that holds your catalog of products (especially if the catalog is changing constantly)
• You have a complicated sales cycle that requires lots of customized forms, pricing tables, et cetera
• You have other business processes already in place and you want your e-commerce offering to integrate into them.
Virtual hosting services give you some of the flexibility of enterprise computing, but what you get depends on the vendor. In general the vendor maintains the equipment and software and sells them in standardized packages. Part of the package includes security, and almost always a merchant account is also an option. Database access is sometimes a part of the package. You provide the web designers and developers to create and maintain your site.
Simplified e-commerce is what most small businesses and individuals are using to get into e-commerce. In this option the vendor provides a simplified system for creating your store. The system usually involves a set of forms that you fill out online. The vendor's software then generates all of the web pages for the store for you. Two good examples of this sort of offering include Yahoo Stores and Verio Stores. You pay by the month for these services.

Tools for E-Trade

Depending upon the purpose with which one is opening a website he may needs various tools for conducting online business venture. Here, is a quick check list for the same:

a. Website needs to be designed in house or not?

In case website needs to be designed in house one needs to check for following things:

1. 
   You need to get experience / training in Web designing. You may opt to use a template /wizard-based tools or hire a designer for the same.
   
2. A good computer having plenty of RAM and hard drive space (6 GB minimum)
   
3. Need to have a web designing software which can be either WYSIWYG (what you see is what you get) or a text editor (use this in case you know html)
   
4. A scanner or digital camera for collecting photos of product or service.
   
5. Image editing software for editing images and illustration software for creating graphics
   
6. Any FTP software like CuteFTP for r uploading files to the Web site
   

b. Website needs to sell products online? In case website is to be used for selling products it needs to be equipped with the following:

1. A merchant account for accepting payments. There are some other options available for accepting payments like traditional methods.
   
2. Shopping cart software : Website should be able to collect shoppers order and update the same in the data base.
   
3. Secure servers: Since online money transaction needs to be done. Website may accept credit card payment or other personal payment information online. In such case secure serve needs to be deployed and maintained.
   
4. Software for tracking inventory and shipping of orders.
   
5. How many products or services need to be listed on the Web site?
   

In case there are many products to be listed on the website. Following points needs to be taken care: a. A database having product names, descriptions, pricing, and photos and other details.b. A system for booking orders.c. A system for inventory management ,tracking shipping orders etc..d. Easy and reliable way of updating and maintaining the database on the website.e. Does the product or service have some requirements like sound, video or animations?In case any of these things are required. One needs to take care of following points.a. An equipment to capture/edit video and/or audio. b. Software (and training) to create good animations c. A broad-band Internet connection (helpful, but not absolutely necessary)How the Pay flow Gateway works? Source:www.Paypal.com1. Customer inputs credit card information on the Online Store. 2. The Payment Gateway encrypts data and securely sends it to the Internet Merchant Account. 3. The transaction is reviewed for authorization. 4. The result is encrypted and sent back through the payment gateway. 5. You get the results and decide whether or not to fulfill the order. Payment processing software
It is usually third party organization, which provides payment processing software, for e.g. monetra, verifone, etc. It is used for getting card transactions authorized and further processed. E –business usually pays monthly fees for processing services. Also it’s extremely vital, for any online transactions e-business must provide adequate security for the card information being transmitted.

FAQ

1. Explain in brief, what is SET?
2. SET is a protocol, true/false?
3. What is dual signature?

SET (Secure Electronic transactions)

When it comes to e-commerce, first thing with pings someone mind is security!! Industry gurus have been putting heart n soul, in order to address this concern. SET was one of endeavor on same lines.

Secure Electronic Transaction (SET) is a standard protocol that is used for securing credit card transactions over insecure networks. With the increase in security concerns over Internet SET has emerged as popular protocol for addressing transactions over Internet. Please note clearly, SET itself is not a payment system. It is a a set of security protocols and formats that enables users to employ the existing credit card payment infrastructure on an open network in a secure fashion!

SET, developed by VISA and MasterCard (Credit card leaders) is based on X.509 certificates having several extensions. [Just FYI: X.509 is an ITU-T standard for a public key infrastructure (PKI. It specifies standard formats many things such as public key certificates, attribute certificates etc…]

SET features

SET has been developed with following features:

• 
  Maintains confidentiality of information: Information is provided only to the concerned
  recipent
  
• SET takes care of Integrity of data
  
• SET employs a particular subset of protocol for carrying out cardholder account authentication
  
• SET employs a particular subset of protocol for carrying out Merchant authentication
  

Understanding SET Protocol SET itself is a family of protocols. The major ones are used for important tasks such as cardholder registration, merchant registration, purchase request, payment authorization, and payment capture. Apart from these major ones there are many minor protocols that are used for conducting tasks like error handling. SET is little complicated than its counterparts such as SSL. Because of this complexity this protocol is hardly used. However, it contains many features of interest such as :

• The model is different from the others. In the registration protocols, the applicant do not need to possesses any digital proof for his identity. He just needs to authenticates himself by filing a simple registration form. Authentication is done outside this protocol when the cardholder’s bank examines the completed form.
  
  
• An important innovation that has been introduced in SET is the dual signature. Like electronic signature dual signature is used to guarantee the authentication and integrity of data. Dual signature links two messages that are intended for two different recipients. A customer needs to send the order information (OI) to the concerned merchant and the payment information (PI) to the corrosponding bank. Through this dual signature the receipent only gets to know information he requires rather then getting any other information of the sender. E.g. The merchant does not need to get information about customer's credit card details where as bank does not need to know the details of the customer's order. However, a link is needed so that the customer can prove that the payment is intended for this order.
  
  
• SET also uses several types of digital envelopes. It can be understood as an encrypted message that uses both secret key and public key cryptography methods. The secret key is used for encrypting and decrypting the message where as the public key method is meant for sending the secret key to the other party. A digital envelope includes two parts:
  
  
  1. One part is encrypted using a public key which contains a fresh symmetric key K and identifying information.
     
  2. Other part is encrypted using K which conveys the full message text.
     
  3. SET employs cryptographic techniques to provide security during a online transaction. Digital certificates and public key cryptography are commonly used to allow parties for authenticating each other and for exchanging information in a secure manner. You must be curious to know how SET works.
     

How it works!
As we all know people today pay for online purchases by usually sending their credit card details to the merchant. There is protocol such as SSL or TLS available that keeps the sender’s credit card details safe from eavesdroppers however are not able to protect merchants from dishonest customers or vice-versa. SET has been developed keeping in mind the limitations of existing protocols. SET requires both cardholders as well as merchants to register before they engage themselves in any transactions. Any card holder can register by contacting a certificate authority. He needs to supply security details and the public half of his proposed signature key to the certificate authority. During the registration authorities verify the applicant. After verification and granting approval authority provides the applicant with a certificate that provides a confirmation that his signature key is valid. All orders and confirmations have a digital signature. This is used to provide authentication in case of any dispute between the parties.

Major participants in a SET system are:

• Cardholder
• Merchant
• Issuer
• Acquirer
• Payment gateway
• Certification authority
Understanding a SET Transaction
Following are the sequence of events that are required for a transaction:
1. Customer needs to obtains a credit card account with a bank which supports electronic payment and SET.
2. The customer will receives an X.509v3 digital certificate which is duly signed by the bank.
3. Merchants have their own certificates.
4. The customer places an order with the Merchant.
5. The merchant sends a copy of its certificate so that the customer can verify that the store is valid
6. The order and payment are sent between the two parties.
7. The merchant then requests for payment authorization.
8. The merchant has to confirms the order.
9. The merchant needs to ship the goods or provide appropriate service to the customer.
10. The merchant needs to requests payment
Key Role Players in a SET Transaction
A SET purchase involves three parties:
1. The cardholder (One who has to pay)
2. The merchant
3. Payment gateway (It is essentially a bank).
Card holder needs to share information as follows with the other two parties:
• The cardholder needs to shares the order information with the merchant. He does not need to provide this information to the payment gateway.
• The cardholder shares the payment information with the payment gateway and not with the merchant.
A set of dual signature is used to accomplish this partial sharing of information among the parties. It allows all parties to confirm that they are handling the same transaction. This is done as follows:
• Each party receives the hash of the withheld information.
• The cardholder needs to sign the hashes of order information as well as payment information.
• Once the card holder signs both hashes each party needs to verify and confirm that the hashes they possess agree with the hash signed by the cardholder.
• Further, the cardholder and merchant needs to compute equivalent hashes which payment gateway needs to compare. After comparing payment gateway needs to confirm their agreement on the details withheld from him.

Simulation Practice Problems

1. There is only one telephone in a public booth of a metro station. Following table indicates the distribution of arrival time and duration of calls:

Time Between arrivals (minutes) 4 5 6
Probability 0.1 .6 0.3

Call Duration (minutes) 3 4 5 6
Probability 0.14 0.6 0.12 0.14

Simulate for 100/500/1000 times. Conduct 3 such trials. It is proposed to add another telephone to the booth. Justify the proposal based on the waiting time of caller.Generate graphs to support your answer.

2. A baker needs to find out the cookies he need to bake each day. The probability distribution for the cookies customers is as follows:
Number of customers/day 7 9 11 14
Probability 0.35 0.30 0.15 0.20



Cookies sold Rs 8 per dozen. The cost Rs 5.5 per dozen to make. All cookies not sold at the end of
the day are sold at half price to a local grocery store. Simulate for 100/500/1000 times. Conduct 3
such trials to identify how many dozen cookies he should bake each day.

3. There is only one telephone in a public booth of in a market. Following table indicates the distribution of arrival time and duration of calls:

Time Between arrivals (minutes) 6 7 8
Probability 0.1 .6 0.3


Call Duration (minutes) 4 5 6 7
Probability 0.14 0.6 0.12 0.14

Simulate for 100/500/1000 times. Conduct 3 such trials. It is proposed to add another telephone to the booth. Justify the proposal based on the waiting time of caller.Generate graphs to support your answer.


4. Students arrive at the university library counter with inter-arrival times distributed as :

Time between arrivals(Minutes) 5 6 7 8
Probability 0.35 0.30 0.15 0.20

The time for transaction at the counter is distributed as:
Time between arrivals(Minutes) 3 4 5 6
Probability 0.15 0.5 0.20 0.15

In case more then two students are in the queue, an arriving student goes away without joining the queue. Simulate the system and determine balking rate of the students.

5. Consider a milling machine having three different bearings that fail in service. The distribution of life of bearings is identical as follows:

Bearing Life(hours) Prob
1000 0.13
1100 0.23
1200 0.25
1300 0.1
1400 .09
1500 .12
1600 0.02
1700 0.06
1800 0.05
1900 0.05

Whenever bearing fails repair person is called and a new bearing is installed. The delay of repair person random that follows distribution given below:

Delay Time Prob
5 0.6
10 0.3
15 0.1

Downtime for mill Rs 10 per min, direct on site repair cost Rs 30 per hour. It takes 20 mins to change one bearing ,30 to change two and 40 minutes to change three. A proposal is to follow following procedure:

Whenever a bearing fail, two bearings are replaced:
a. One that has failed
b. Another one out of other two remaining bearings with longest operational time.

Simulate and evaluate the proposal. The total cost per 10,000 bearings hours will be used as the measure of performance.

6. Students arrive at the university library counter with inter-arrival times distributed as :

Time between arrivals(Minutes) 5 6 7 8
Probability 0.35 0.30 0.15 0.20

The time for transaction at the counter is distributed as:
Time between arrivals(Minutes) 3 4 5 6
Probability 0.15 0.5 0.20 0.15

In case more then two students are in the queue, an arriving student goes away without joining the queue. Simulate the system and determine balking rate of the students.



7. Consider a situation of a company that sells refrigerators. The system they use to maintain inventory is to review the situation after fixed number of days say N. and make a decision about what is to be done. The policy is to order upto a level (order up to level say M) using following relationship:

Order Quantity =(Order up to level) – Ending Inventory + Shortage Quantity

No. of refrigerators ordered each day is randomly distrubted as follows:
Demand probability
0 0.1
1 0.25
2 0.3
3 0.21
4 0.09

Lead Time (number of days after the order is placed to the supplier before arrival) is distributed as follows:

Lead time (days) probability
1 0.6
2 0.3
3 0.1

Simulate the order up to inventory system for 100,1000 trials. Assume M=11,N=5. Check efficiency of the system.

8 . Estimate by the simulation, the average number of lost sales per week for an inventory system that functions as follows:

a. Whenever inventory level falls to or below 10 units, an order is placed,Only one order
can be outstanding at a time
b. The size of each order is equal to 20-I where I ,inventory level when order is placed.
c. If a demand occurs during a period when inventory level is zero, the sale is lost.
d. Daily demand is distributed as follows:

Demand Probability
0 0.1
1 0.25
2 0.3
3 0.21
4 0.09
e. Lead time distributed normally b/w 0-5 days (integer) only.
f. Simulation starts with 18 units in inventory.
g. Assume that orders are placed at the close of business day and received after the lead time has occurred. Thus, if lead time is one day, the order is available for distribution on the morning of the second day of business following the placement of the order.
h. Let simulation run for 5 weeks.



9. There is only one ATM in market. Following table indicates the distribution of arrival time and duration of calls:

Time Between arrivals (minutes) 4 5 6
Probability 0.1 .6 0.3



Call Duration (minutes) 3 4 5 6
Probability 0.14 0.6 0.12 0.14

Simulate for 100/500/1000 times. Conduct 3 such trials. It is proposed to add another ATM to the market. Justify the proposal based on the waiting time of caller. Generate graphs to support your answer.


10. A shopkeeper needs to find out the breads he need to bread each day. The probability distribution for the cookies customers is as follows:

Number of customers/day 7 9 11 14
Probability 0.35 .30 0.15 0.20

Bread sold Rs 15 per pack. It cost Rs 5.5 per pack. If not sold at the end of the day are sold at half price to a local grocery store. Simulate for 100/500/1000 times. Conduct 3 such trials to identify how many dozen cookies he should bake each day.


11. Consider a milling machine having three different bearings that fail in service. The distribution of life of bearings is identical as follows:

Bearing Life(hours) Prob
1000 0.13
1100 0.23
1200 0.25
1300 0.1
1400 .09
1500 .12
1600 0.02
1700 0.06
1800 0.05
1900 0.05

Whenever bearing fails repair person is called and a new bearing is installed. The delay of repair person random that follows distribution given below:
Delay Time Prob
5 0.6
10 0.3
15 0.1

Downtime for mill Rs 10 per min, direct on site repair cost Rs 30 per hour. It takes 20 mins to change one bearing ,30 to change two and 40 minutes to change three. A proposal is to follow following procedure:

Whenever a bearing fail, all bearings are replaced. Simulate and evaluate the proposal. The total cost per 10,000 bearings hours will be used as the measure of performance.

12. Consider multiple hard disk computer system having 4 disks that fail in service. Disk having bad sectors need to be replaced. The distribution of life of different disks is given below:
Disk Life(years) Prob
10 0.13
11 0.23
12 0.25
13 0.1
14 .09
15 .12
16 0.02
17 0.06
18 0.05
19 0.05

Whenever there is a bad sector in the disk that disk is replaced by the hardware engineer. Hardware engineer need to be called from outside. He may take 1/2/3 days to arrive random that follows distribution given below:
Delay (days) Prob
1 0.6
2 0.3
3 0.1

Downtime for the computer system Rs 100 per min, direct on site cost of replacement by hardware
engineer is Rs 30 per hour. It takes 20 mins to change one disk ,30 to change two, 40 minutes to change three and 60 minutes to change four. A proposal is to follow following procedure:

Whenever a disk has bad sector replace all disks in anticipation. Simulate and evaluate the proposal. The total cost per 10,000 bearings hours will be used as the measure of performance.


13. Consider the simulation of a management game. There are three players A,B,C. Each player has two strategies which they play with equal probabilities. The players select strategies independently. The following table gives the payoff.

Strategies A (payoff) B (Payoff) C (payoff)
A1-B1-C1 10 -5 5
A1-B1-C2 0 8 2
A1-B2-C1 9 3 -2
A1-B2-C2 -4 5 9
A2-B1-C1 6 1 3
A2-B1-C2 0 0 10
A2-B2-C1 6 10 -6
A2-B2-C2 0 4 6

Simulate 100 players and determine payoff.


14. Consider a milling machine having three different bearings that fail in service. The distribution of life of bearings is identical as follows:

Bearing Life(hours) Prob
1000 0.13
1100 0.23
1200 0.25
1300 0.1
1400 .09
1500 .12
1600 0.02
1700 0.06
1800 0.05
1900 0.05

Whenever bearing fails repair person is called and a new bearing is installed. The delay of repair person random that follows distribution given below:
Delay Time Prob
5 0.6
10 0.3
15 0.1
Downtime for mill Rs 10 per min, direct on site repair cost Rs 30 per hour. It takes 20 mins to change one bearing ,30 to change two and 40 minutes to change three. A proposal is to follow following procedure:

Whenever a bearing fail, two bearings are replaced. Simulate and evaluate the proposal. The total cost per 10,000 bearings hours will be used as the measure of performance.


15. A baker needs to find out the packets of bread he need to bake each day. The probability distribution for the cookies customers is as follows:
Number of customers/day 7 9 11 14
Probability 0.35 0.30 0.15 0.20

Cookies sold Rs 8 per dozen. The cost Rs 5.5 per dozen to make. All cookies not sold at the end of the day are sold at half price to a local grocery store. Simulate for 100/500/1000 times. Conduct 3 such trials to identify how many dozen cookies he should bake each day.


16. Students arrive at the university library counter with inter-arrival times distributed as:

Time between arrivals(Minutes) 5 6 7 8
Probability 0.35 0.30 0.15 0.20

The time for transaction at the counter is distributed as:
Time between arrivals(Minutes) 3 4 5 6
Probability 0.15 0.5 0.20 0.15

In case more then two students are in the queue, an arriving student goes away without joining the queue. Simulate the system and determine balking rate of the students.

17. Trucks are used to carry components between two assembly stations A and B. Three types of components (C1,C2,C3) from station A are assembled at station B. The interarrival time of C1,C2,C3 are:

Component Interarrival Time(minutes)
C1 7+/-2
C2 3+/-1
C3 8+/-3

The truck can take only three components at a time. It takes 90 seconds to travel(to and fro) and 30 seconds to unload at station B. The truck waits at station A till it get full load of three components. Simulate the system for 1 hour and determine the average waiting time of three components.

18. There is only one PCO in market. Following table indicates the distribution of arrival time and duration of
service:

Time Between arrivals (minutes) 4 5 6
Probability 0.1 .6 0.3


Call Duration (minutes) 3 4 5 6
Probability 0.14 0.6 0.12 0.14


Simulate for 100/500/1000 times. Conduct 3 such trials. It is proposed to add another PCO booth to the market. Justify the proposal based on the waiting time of caller. Generate graphs to support your answer.

Simulation and Modeling FAQ continued

1. Discuss the usage of DEVS in detail?
2. Describe the steps involved in a simulation study?Illustrate with a relevant example
3. Explain the four steps involved in the model building process?
4. Simulation can be used to solve traffic problems at major intersections?Explain the steps involved to carry this simulation study?
5. How can simulation be used to study the queuing systems?
6. Describe pictorially the arrival and departure in a queuing system?
7. Give an example of Single channel queue. How can you use simulation to study such a system?
8. What according to you are the performance measures required to analyze a queuing system?
9. How will you calculate following performace measures for a sing server queuing system

a. Average waiting system.
b. Probability a customer has to wait.
c. probability of idle server
d. Average service time
e. Expected service time
f. Average time between arrivals.
g. Average time customer spends in the system.
h. Average waiting time for those who wait.

10. How can simulation be used to solve inventory problems. Discuss with a case study?
11. Explain how simulation can be used to solve lead time problems in inventory?
12. Describe briefly various concepts involved in discrete event simulation?
13. Discuss the event scheduling/time advance algorithm in detail?
14. what are the various world views available to model a system for simulation? Illustrate with example appropriate usage of different word view?
15. How exactly a future event list should be implemented? Explain pros and cons of using various kinds of implementations?








c
b

Simulation & Modeling FAQs

1. Discuss the advantages and disadvantages of Simulation?
2. Discuss with example case when not to use Simulation?
3. What according to you are the real world problems where you find simulation is the most appropriate tool?
4. Discuss the role play of simulation in following fields?
1. Business Processes?
2. Manufacturing Application
3. Military Applications
4. Logistics and Supply chains
5. Discuss system and its components in detail?
6. Differentiate the following


a. Open System and Closed System
b. Exogenous and Endogenous System
c. Discrete and continuous system
d. Static Vs Dynamic system
7. what are the different types of models/
8. Name the entities,attributes,activities,events and state variables for the following systems
a. College library
b. Mobile Call center
c. Hospital Ward
d. Departmental Store
e. Airport ticketing

Simulation & Modeling (LAB AND THEORY ASSIGNMENTS)

Simulation & Modeling (ASSIGNMENTS)

TRANSPORTATION PROBLEM

E-Commerce Notes # 1-5

FTP - File transfer Protocol
ISP - Internet Service Provider
DNS - Domain Name Server

Revolution Change
Digital Enabled Transaction -All transactions that are mediated by digital technologies

Commercial
Exchange of value between or across organizational or individual boundaries in return of a product or service for a commercial transactions

What is the difference between E-Commerce & E-Business

E-Business
Digital enablement of transaction & process within a firm involving information system under control of firm. e.g. : online inventory control, LMS - Leave Management System, EMS - Employee Management System.

E-Business turns into E-Business when there is a commercial value added to it.

<<DIAGRAM>>

Information Asymmetry
Geographical Boundaries
Information about price/cost/fees are hidden from consumers creating a profitable hidden information asymmetry. This creates a disparity in relevant market information that confuses the customers.

The traditional system is trapped by social, geographical boundaries. We can say that selling is conducted in well insulated channels.

Why E-Commerce ?
    1- Geographical Trapping
    2- Information Asymmetry
   
Unique features of E-Commerce:
    - Ubiquity
    - Global Reach
    - Universal Standards
    - Richness
    - Interactivity
    - Information Density
    - Personalization / Customization

Ubiquity - Anytime / Anywhere availability
E-Commerce is ubiquitous because it is available almost everywhere internet web technology can be freely used at employee. So it liberates market from physical countries that exist in the traditional media.

// Market Space is market place extended beyond traditional boundaries.

Reduces transaction cost
    - Cost of participants in the market
    - To transact it's no more necessary to spend time travelling in the marketplace.
    - It lowers the cognitive energy required to transact in the marketplace.
   
E-Commerce permits commercial transaction across boundaries both conveniently & cost effectively.

Global Reach
Measure of reach is defined as number of users a business can entertain.

Market space of E-Commerce can be expanded easily.

Universal Standards
Its benefits :
    - Lowers entry cost - Cost a merchant needs to pay to bring these goods in the market.
    - Reduces search cost - Effort required to search a suitable product.
    - Creates a market space where prices and products can be inexpensively be displayed
    - Price discovery in faster & more accurate
    - Easy to find supplier's prices, delivery terms of a specific product in the world.
   

Five C2C web sites :-
    - Ebay
    - 99acres
    - Sulekha
    - Magicbricks
   
P2P - Enables internet users to share files & computer resources directly without going through a central web server. No intermediaries are required

Example :-
Gnutella - It's a P2P application that permits users to directly exchange musical tracks, without any change. Since 1999 entrepreneurs had been adopting P2P technologies to earn online. Napster had been a very popular P2P application for sharing music files online. Partially P2P as it uses a central database of users sharing files

M-Commerce :- Is facilitated by the users of wireless, digital devices. Once connected, mobile can conduct many types of transaction including trading, shopping, banking & more.

Limitations of E-Commerce :-
    1) Requires internet connection, digital devices, etc.
    2) Security vulnerability
    3) Lack of awareness
    4) Attraction of traditional shopping

Simulation Assignment Allocation

Sno. Roll No. Assignments
1 2032,4501 Simulation of computer system
2 4502,4506 Web Simulation
3 4507,4568,4538 Simulation of Queuing System and its applications e.g. Food Bazaar
4 4508,4536,4546 Input Output modeling for simulation
5 4509 Random Number generation for simulation
6 4510,4525,4520 Application of Simulation for solving network flow problems
7 4511,4543 Simulating Car Parking
8 4513,4533,4531 Monte-carlo Simulation
9 4514 Simulating grocery Shop
10 4516,4535,4551/08 Simulation of websites to improve traffic for a website
11 4515,4528,4529 Understanding GPSS
12 4518,4554,4566 Gaming Simulation
13 4519,4524 Conducing web simulation on e-commerce portals
14 4530,4551,4556 Understanding Object oriented simulation
15 4534,4557 Learning to solve Problems using simulation
16 4539,4542 Developing a Simulation Database: Studying case studies/FAQs
17 4540,4547,4543 Online Traffic Monitoring system
18 4541,4545,4555 Application of Simulation for Forecasting
19 4537,4532,4521 Studying Simulation languages like SIMSCRIPT,GPSS,MODSIM
20 4550,4563 Solving problems for input modeling
21 4523,4552 Study applications of random generators in simulation and other
fields illustrating by solving problems
22 4560,4562 Application of Simulation for security and anti-spamming
23 4522,4526 Understanding DEVS
24 4532,4533,4568 Using general purpose simulation language for problem solving
25 4535,4538,4541 Developing simulation program in C [pros & cons
26 4544,4548 Output Analysis for a single model
27 4549,4552 Comparison & Evaluation of Alternative system designs
28 4553,4558 Simulation of computer networks

E-Commerce Notes #12

Custom Search

• UDP - User datagram protocol (most used protocol). www is based on this protocol.
• Network Interface Layer is a club of physical layer and protocol of data packet flow.
• DHCP - Dynamic Host Controller Protocol, provides dynamic IP address to the once requesting for it.
• ICNM - Governs the IP address.
• Routers - Helps packets to reach the destination (in local level), bridges (in regional), gateways (in national level )
• Transport Layer decides the how they are going to flow, like session, security, and data path.
• Application Layer is which has the interface with the user, which arranges the data packets in the correct order.

Important topics :

• Layers of TCP/IP

• Their functionality
• Benefits of using TCP/IP

• Definition of IP address, Domain name, DNS, route servers - are the central directories that list all the domain names that are currently in use. The DNS server consults the route server in case it is not able to find the destination - Domain name.

• Governing bodies of internet are :
• IAB - Internet Architecture Board - Defines the overall structure of internet.
• ICANN - Internet Corporation for Assigned Names and Numbers - Assigns IP addresses
• IESG - Internet Engineering Steering Group - Looks over the standard settings
• IETF - Internet Engineering Task Force - Forecasts the next step in the growth of internet
• ISOC - Internet Society - Consortium of govt. agencies, non-profit organizations and corporates that monitor the internet policies and practices.
• W3C - World Wide Web Consortium - Finalizes the language standards.

• Important Internet protocols
• HTTP - Hyper text Transfer Protocol
• SMTP - Simple Mail Transfer Protocol
• IMAP - Instant Message Access Protocol
• POP - Post Office Protocol
• FTP - File Transfer Protocol
• SSL - Secure Socket Layer
• Telnet - A terminal emulation program that runs in TCP/IP. One can run the telnet from the client machine and emulate another system
• PING - Packet Internet Grouper - Check the connectivity between a host and client.
• FINGER - Helps to who is logged, how long are they connected.

• Intranets and Extranet - Intranet is a TCP/IP network located within a single organization for the purpose of the communication and information processing. Unlike intranet, in extranet a firm provides outsiders permission to access the internal network
• NSPs - Network Service Providers are one of the hubs which own and control one of the major networks which form the backbone of the internet. The backbone is like a pipeline that transfers data through out the world in milliseconds The bandwidth measures how much data can be transferred throughout the network in a fixed amount of time.
• NAP - Network Access Points - These are the hubs where the backbone intersects the regional and the local network
• MAE - Metro Area Exchange - These are the hubs where the backbone intersects the regional with // Check this : other regional networks
• RH - Regional Host

Internetcan also be characterized by hourglass modulus structure having four layerswith the lower layer containing bit carrying infrastructure including cablesand switches and upper layer containing the user applications such as e-mailsand web. The narrow vast are the transportation protocols such as TCP/IP. Thefour layers are :

• Network Technology substrate
• Transport services and the representation standards
• Middleware services
• Applications

WWWis one of the service internet. We require internet connection andtechnologies. Markup language is used to present information online.

Firstmarkup language is SGML - Standardized Generalized Markup Language.

HTML- HyperText Markup Language

XML- eXtensible Markup Language

Webserver plays active role, when the client requests for dynamic  web pages

Hyperlinkis the most important component of web.

Applicationsof web :

• E-mail
• Search Engine
• Intelligent Bots - Software programs that gather or filter information and provide it to the user. e.g. - shopping bot.
• Instant Messaging / Chat
• Music / Video transmission
• VoIP
• WAP - Wireless Access Protocol (Language WML - Wireless Markup Language)

Limitations of Internet I

Attenuation

BandwidthLimitation

Qualityof service limitation

NetworkArchitecture limitation

Languagedevelopment limitation

GPRS - General Packet Radio Switching