Networking Assignment Help: What specific steps can be taken to improve security in WLANs...

Q)What specific steps can be taken to improve security in WLANs?

Sol:

 The below steps can be taken to improve the security in WLANs:

a) Initially wireless network has to be authorized and authenticated.

b) Also all the users try to get connected to that particular has to be authorized and authenticated.

c) Every user connected to the network has to be uniquely identified by their own unique username and password.

d) Multiple users with same username and password should not be allowed to connect to the network.

e) Every user has to be properly disconnected so that no one in queue must be able to continue to get connected to the network with their username and password.

Think and Answer Assignments: Minicase IV Household Wireless page....

Q)Your sister is building a new two story house which measures 50 feet long by 30 feet wide and wants to network her family’s three computers together. She and her husband are both consultants and work out of their home in the evenings and a few days a month.  Each has a separate office with a computer, plus a laptop from the office that they occasionally use. The kids also have a computer in their playroom. They have several options for networking their home:

a) Wire the two offices and playroom with Ethernet cat5e and put in a 100Base-T switch.

b) Install one Wi-Fi access point ($85) and put Wi-Fi cards in the three computers (the laptops already have Wi-Fi)

c) Any combination of these options

There are many possible solutions to this problem.  What would you recommend, considering their current hardware configuration as well as potential expansion? Justify your recommendation.           

Sol:

The best possible solution is to go for installation of Wi-Fi access points followed by installation of Wi-Fi cards for the desktop computers. Anyways laptops will definitely have Wi-Fi inbuilt so there is no need for separate installation of the cards in laptops. The reason behind this is looking at the future definitely the desktops are getting replaced by laptops. Also laptops are portable, which means we can carry them any where we need but if they are connected to some network cables then we will not be able to access the network wherever we carry the laptops. Also in case of desktops if we place it in 1st floor but tomorrow we need it in the last floor then there is need to work on the network connectivity in it only labor is involved in shifting but network connectivity is always there since it is independent of the location within the office campus or two story house limits. Hence the recommendation here is to go for Wi-Fi connection.

Networking Homework Help: There is an ever growing range of physical media being offered such as fiber...

Q)There is an ever growing range of physical media being offered such as fiber, coax, satellite, IP over power lines, a number of wireless technologies, and more. Recently, the telephone companies announced 4G wireless communications and the IEEE has WiMax at Gigabit rates. What criteria would you use to select technologies for your business and for your home?

Sol:

The following are the criteria being used to select technologies for my business:

a) Multiple connections with maximum speed.

b) Higher bandwidth with lesser price.

c) Unlimited downloads with no additional charges.

d) Unlimited access within the coverage area irrespective of the machines being used.

e) Full time high speed networks without any congestion.

The following are the criteria being used to select technologies for my home:

a) Not more than two connections at a time.

b) Very lesser cost, irrespective of download limits.

c) Limited access but reduction in the monthly bill.

d) Moderate speed and bandwidth, irrespective of the congestion.

e) Lesser monthly rentals provided there are additional charges for download if it crosses the available limit.

General Assignment Help: How to define a portfolio of Outsourced information technologies services...

Q) How to define a portfolio of Outsourced information technologies services??

Sol: 

Portfolio of Outsourced Information Technologies services can be defined as identifying and understanding the customer requirements, also providing a way to communicate the value that the IT organization delivers to the business. The portfolio of IT services also allows the IT organization to say to the business, “Here is what we deliver to you”. Ultimately, it is the list of what customers ‘buy’ from the IT organization by paying the Organization.

Read and Answer: The International Centre for Radio Astronomy Research...

1) The International Centre for Radio Astronomy Research

Sol:

The International Centre for Radio Astronomy Research is a collaborative centre placed in Perth, Western Australia. They are already achieving research excellence in both astronomical science and engineering. The International Centre for Radio Astronomy Research has grown steadily from its launch in September 2009. An equal joint venture between The University of Western Australia and Curtin University, International Centre for Radio Astronomy Research has strong support from the West Australian as well as Australian governments and is working very closely with industry and research partners in Australia and in the entire world. Wireless internet (WIFI) inventor honored Curtin University has been recognized as Dr John O’Sullivan’s ground breaking work in astronomy and wireless technologies by bestowing John with an Honorary Science Doctorate. The latest telescope puts focus on high school discoveries where a new internet telescope was launched by State Education Minister Dr Elizabeth Constable at The Western University of Australia. Also
Sky Noise and Sensitivity Studies of Array Configurations and Antenna Elements were done for the Low-Frequency Band of the SKA.

Questions:

a) What is WIFI?

b) Expand ICRAR?

c) Internet telescope was launched by whom?

d) Who invented wireless internet?

Sol:

a) Wireless internet/wireless LAN.

b) International Centre for Radio Astronomy Research.

c) Dr. Elizabeth.

d) Dr John O’Sullivan

Read and Answer: De-noising sea noise data....

1) De-noising sea noise data

This work presents De-noising sea noise data and also how data from a marine seismic survey, which is highly contaminated by noise, was de-noised through the use of a time-frequency filter. In addition to the present standard work flow designed to remove cavitation noise, strumming noise and swell-noise. We introduce a new approach to track seismic interference. This is done by applying time-frequency de-noising on the slowness that gathers. As a motivation and background for the processing we also explain some of the techniques behind the generation of the many different noise types.

The end story is that even in case low if there is a low quality input data then also it can be turned into high quality seismic sections. Even though the dataset used is only one, the results and its methodologies represented here are considered to be general, and should be definitely applicable to a large number of seismic surveys.

Questions:

a) Name the two components which seismic data consists of? 

b) What is the second problem in this dataset?

c) What is the frequency range of swell noise?

d) What is the frequency range of hydrostatic pressure variation noise?

Sol:

a) signal and a noise component

b) Swell-noise

c) (1-10(15)Hz)

d) (0-1(2)Hz)

Read and Answer: Passive acoustic techniques to study sound producing fish species...

1) Passive acoustic techniques to study sound producing fish species

A wide variety of taxa fish produce sound. The behavior of Sound production gives an opportunity to study and analyze various aspects of fish biology, such as habitat selection and spawning behavior, in a very non-invasive manner. Passive acoustics is an active area of research called ichthyologic research. However, fish bio-acousticians have not published their research details in the fisheries literature. Therefore, fisheries scientists may not be aware of progress being made in this field completely or the potential uses for acoustic techniques passively. The physiological, behavioral and evolutionary aspects of sound production by fishes generally investigate the patterns of research publication on sound production by the fish and also review the literature which is based on the passive acoustic methods application to the research of fisheries and finally predicts and tells different ways of passive acoustic surveys which is being designed to optimize the quality and quantity of information obtained. Passive acoustic methods can be definitely attractive as well as alternative or it may supplement to the other traditional fisheries based on assessment techniques since they are non-invasive, and also can be conducted at low cost, which covers a large study area at temporal resolution and high spatial.

Questions:

a) Name the fish which produces sound?

b) Which are the three aspects of sound production?

c) Which acoustic method can be attractive?

d) What can be the Passive acoustic methods?

Sol:

1. Taxa
2. Physiological, behavioral and evolutionary aspects.
3. Passive acoustic method.
4. non-invasive

Read and Answer: The International Centre for Radio Astronomy Research...

1) The International Centre for Radio Astronomy Research

The CSIRO Wireless LAN story

CSIRO’s wireless LAN is one of the most leading technologies, and also most of you are already aware of the story. The technology lies at the heart of the most popular way of connecting computers without wires which is now known as wireless LAN. CSIRO has reminded very important and also lucrative always in terms of getting things done in the better manner. The Science and technology Industry Endowment Fund launched has been made possible by the success of CSIRO’s wireless LAN technology. Hence we can pay a particular tribute to everyone those who have made the Science and Industry Endowment Fund possible by creating CSIRO’s wireless local area network technology. Recently, CSIRO has sharpened its focus very well on Australia’s greatest opportunities and challenges through its National Research Flagships. CSIRO’s wireless LAN technology ranks as a major achievement in Australia, and it would be great enough to see significant objects related to the wireless LAN story which is being researched these days.

Questions:

a) Name the inventers of CSIRO WLAN?

b) Commercial board of CSIRO is chaired by?

c) Where was the CSIRO research carried out?

d) In which place in Australia the CSIRO WLAN was launched?

Sol:

a) Terry Percival, John Deane, Graham Daniels, Diet Ostry and John O’Sullivan.

b) Dr Terry Cutler.

c) In Australia.

d) National Museum of Australia.

The total number of partitions of a k-element...

Q) The total number of partitions of a k-element
   set is denoted by B (k) and is called the k-th Bell number.

    Thus B (1) = 1and B (2) = 2.
   Need to find B (k) for k = 4, 5, 6.

Sol:

We know that,

Where,

Is the Binomial Coefficient.

It is given by:

It’s given that B (0) =1; B (1) =1; B (2) =2

Hence for n=3, from the first formulae

B (3) =C (2, K) B (K) where K=0 to n-1

B(3)=C(2,0)B(0)+ C(2,1)B(1)+ C(2,2)B(2)

From the second formulae, C (2, 0) =2! /0! (2-0) = 1

C (2, 1) =2; C (2, 2) =1

Hence,

B (3) =1*1+2*1+1*2=5

For n=4,

B(4)= C(3,0)B(0)+ C(3,1)B(1)+ C(3,2)B(2) + C(3,3)B(3)

        = 1*1+3*1+3*2+1*5= 15

Similarly,

For n=5,

B (5) = 52

For n=6,

B (6) = 203

Assignment Help: Phases of the Moon Exercise...

In this exercise, you will investigate the cause of the phases of the Moon. The figure below shows an orbital diagram of the Earth-Moon system as viewed from above the Earth's north pole. Light from the Sun is coming from the left. Note that the drawing is not to scale.

Section I

Shade in the part of the Moon that is in shadow and the part that is not observable from Earth in each of the eight numbered positions. The first has been completed as an example. (Use dark shading for the shadow, light cross-hatch for the unobservable side.) 

To be continued based on the request, please feel free to contact us or comment on this post for more info on this question/answer

Write-Ups Assignment Help: What is a little-know secret to the profitability of Amazon.com?

The below are few of the topics on which the write-ups of 300 to 500 words are expected:

1) What is a little-know secret to the profitability of Amazon.com?

2) Which of these characterized the strategies is the early days (and somewhat, still today) of electronic commerce?

3)Q)“Words carry the message. They would carry the same meanings with or without paragraphing. Therefore, paragraphing has no effect on communication.” Discuss your view of this statement and provide an example which supports your analysis. 

4)What is access matrix? For what purpose is access matrix used in general purpose OS?

4)Many people feel that the American government is out of touch with its public. Look at the branches of government and analyze this statement. 

Need an answer, Please comment on this post!!!

Write-Ups Assignment Help: JIT logistics/supply chain management for what...

Q) JIT logistics/supply chain management for what (now defunct) America automaker.

Sol:

JUST-IN-TIME LOGISTICS SUPPORT IS USED FOR THE AUTOMOBILE INDUSTRY since JIT drastically reduces the investment as well as also the total cost of the operation. In the early 1970s the United States automobile industry realized that the advantage of adopting the JIT would bring the US automakers where they were carrying $775 worth of the work in the process inventory for each of the car they built, but the Japanese carried only $150 of the amount. The only very existence of the Unites states auto industry which depended on the adopting of the JIT philosophy. Very efficient way of transportation methods were one of the critical to the effective JIT process.

Key issues of the transportation before the JIT include plant locations, were the role of the transportation along with the deregulation as well as the transportation regulation. The placement of the plants also changed as a solution of the implementation of the JIT.

Homework Help: What is the rms speed of each helium atom...

Q)The molecular mass of helium is 4 g/mol, the Boltzmann’s constant is 1.38066 ×
10−23 J/K, the universal gas constant is 8.31451 J/K · mol, and Avogadro’s number
is 6.02214 × 1023 1/mol. Given: 1 atm = 101300 Pa.
What is the rms speed of each helium atom?
Answer in units of m/s.

Sol:

The average kinetic energy is given by:

KE_atom = (PV)/N

Number of atoms (N)= Avogadro's number (A) * n
where N = A*n = A*(PV/RT)

N = 6.02214 x 10^23 atoms/mole * (96235 Pa * 0.01414 m^3) / (8.31451 J/K-mol * 285.15 K)
N = 3.456 x 10^23 atoms

KE_atom = (96235*0.01414 /3.456 x 10^23 )J/atom
      = 3.94 X 10^-21 J/atom

KE_a = (1/2) m v^2
m = (Molecular Mass (Mm) / A)
m = (0.004 kg/mole / 6.02214 x 10^23 atoms/mole)
m = 6.42 x 10^-27 kg/atom
v^2 = (2 KE_a)/m
v = sqrt((2 KE_a) / m)
v = sqrt((2 * 3.94 X 10^-21 J/atom) / 6.42 x 10^-27 kg/atom)
v = 1108 m/s

Homework Help: What is the average kinetic energy of each helium atom...

Q)The molecular mass of helium is 4 g/mol, the Boltzmann’s constant is 1.38066 ×
10−23 J/K, the universal gas constant is 8.31451 J/K · mol, and Avogadro’s number
is 6.02214 × 1023 1/mol. Given: 1 atm = 101300 Pa.
What is the average kinetic energy of each helium atom?
Answer in units of J.

Sol:

The average kinetic energy is given by:

KE_atom = (PV)/N

Number of atoms (N)= Avogadro's number (A) * n
where N = A*n = A*(PV/RT)

N = 6.02214 x 10^23 atoms/mole * (96235 Pa * 0.01414 m^3) / (8.31451 J/K-mol * 285.15 K)
N = 3.456 x 10^23 atoms

KE_atom = (96235*0.01414 /3.456 x 10^23 )J/atom
      = 3.94 X 10^-21 J/atom

Networking Assignment Help: Explain the RSA Public Key Encryption Scheme in detail...

Q)Explain the RSA Public Key Encryption Scheme in detail.In particular ,how do the encryption and decryption algorithms work? Explain also how you choose the public and private keys.Suppose a user picks n=17*5; i.e .,p=17 and q=5.How should he pick the public key and the private key (i.e., d and e)? Give the encryption and decryption algorithms.

Sol:

RSA Public Key Encryption which was invented by Cocks (GCHQ), independently, by Rivest, Shamir and Adleman (MIT). Say for example let ‘p’ and ‘q’ is the two large prime numbers.

Let N = p*q be the modulus, then Choose ‘e’ relatively prime to (p-1)*(q-1)

Find d such that e*d = 1 mod (p-1)*(q-1)

Here the Public key is given by (N, e) and the Private Key is given by ‘d’.

The encryption as well as the decryption algorithm works as follows:

To encrypt the message M compute

C = M^e mod N

And to decrypt the message C compute

M = C^d mod N

Please recall that e and N are public, hence if attacker can factor N, then he can definitely use ‘e’ to easily find the value of ‘d’ since e*d = 1 mod (p-1)*(q-1)

Factoring the modulus will break the RSA, therefore it is not known that whether the factoring is the only one way to break RSA.

Suppose a user picks N=17*5; i.e., p=17 and q=5.

Hence N= 85,

(P-1)*(q-1) = 16*4=64

Choose ‘e’ such that it is relatively prime to 64. Hence e=5

Find‘d’ such that e*d = 1 mod 64, we find that d = 7 works

Public key: (N, e) = (85, 5)

Private Key: d = 7

Encryption as well as decryption algorithm works as follows:

Public key: (N, e) = (85, 5)

Private Key: d = 7

Suppose message M = 8

Cipher text C is computed as

C = M^e mod N = 8⁵ = 32768 = 17 mod 85

Decrypt C to recover the message M by

M = C^d mod N = 17⁷ = 410,338,673

= 12,434,505 * 85 + 8 = 8 mod 85

Homework Help: What is the speed of the block when the spring has been compressed...

A block with a mass of 0.148kg is traveling at 8.4m/s on a horizontal,frictionless surface when it hits a spring with a spring constant of 722 N/m. What is the compression of the spring when the block has slowed to 3.9 m/s?What is the speed of the block when the spring has been compressed by 0.049m?

Looking for an answer to this question, then comment on this post!!!

Physics Assignment Help: How much work is done moving a...

Q)How much work is done moving a 2.5 kg book to a shelf 3.0 m high?

a.What is the potential energy of the book in #7 above?
b.If the book in #7 above, falls off the shelf, how much kinetic energy will it have when it hits the floor

Sol:

Work done = Force*displacement

Force=m*g=2.5*9.8=24.5N

Work done= 24.5*3=73.5Joules

a) Potential energy = work done= m*g*h= 73.5Joules

b) Kinetic energy when it hits the floor will be at t=0,

V=U + at=0+9.8*0=0

KE= ½*m*v² = 0J

Chemistry Assignment Help: What is the equilibrium concentration of H2S...

Q)Kc = 2.6 × 10^8 at 825 K for the reaction

2H2(g) + S2(g) <===> 2H2S(g)

The equilibrium concentration of H2 is 0.0020 M and that of S2 is 0.0010 M. What is the equilibrium concentration of H2S?

1. 0.0010 M
2. 1.02 M
3. 10 M
4. 0.10 M

Sol:

K_c = [H2S]²/[H2]²*[S2]

2.6*10⁸ = [H2S]²/[0.002]²[0.001]

Hence equilibrium concentration of [H2S]= 1.02M

Physics Homework Help: Compare the kinetic energy of an...

Q) Compare the kinetic energy of an 900 kg car travelling at 30 m/s, and a 1,800 kg car at the same speed.

 Sol:

Kinetic energy is given by, KE = 1/2mv²

Where ‘m’ is the mass, ‘v’ is the velocity.

Case1:

Given m=900kg, v=30m/s

(KE) ₁= 0.5*900*30²=405000Joules

Case2:

Given m=1800kg,v=30m/s

(KE) ₂= 0.5*1800*30²=810000Joules

Therefore, (KE) ₂ = 2(KE) ₁

Homework Help: what is the new pressure in the tank?

Gas is confined in a tank at a pressure of 10 atm and a temperature of 13◦C. If 38 percent of the gas is withdrawn and the temperature iGas is confined in a tank at a pressure of 10 atm and a temperature of 13◦C. If 38 percent of the gas is withdrawn and the temperature is raised to 70◦C, what is the new pressure in the tank? Answer in units of atm.s raised to 70◦C, what is the new pressure in the tank?
Answer in units of atm.

Sol:

Here we will make use of the formulae:

P2 = P1*(V1/V2)*(T2/T1), where V2 = 0.62(V1), T1= 13+273= 286K

T2= 70+273= 343

P2 = 10*1.6129*343/286 = 19.34atm