1.For x(t)=cos(6t)*sin(4t), inMatlab (a) Apply Euler’s formla to determine the frequencies of x(t).
(b) Plot the magnitude and phase of its Fourier transform. Think about what time interval and duration that you should use. In doing the plots, use frequency for your x-axis instead of index.
(c) Reconstruct x(t) from Euler’s formula in Matlab and also by using ifft.
(d) Compare the original x(t), the reconstructed x(t) ‘s in (b) by plotting the three curves in one plot (use different symbols/colors to distinguish the three). The three should be the same!
Sample Solution
and dedication to its human resource management by investing 20million on training facilities. This was paid off at 1973 when the airline was ranked third in the Far East Asian region. The company then are force to conduct cost cutting program to struggle with surge of oil price on 1973~1977. Surviving this, in 1977 the airlines joint operation with British Airway to provide Concord jet service between Singapore and London, the service was terminated in 1980. This however was deem a marketing success as Singapore Airline were make famous around the globe with this achievement. At the same period, new Changi Airport was constructed, leading to a higher service standard being provided by Singapore Airline. This has paid off and Singapore Airlines were the top preference in Asia-Pacific Region in 1981.
The airline follows a steady internal growth strategy in the 1980s, expanding its size, renewing fleet and adding route. SIA was privatised on 1985, listing on Singapore stock exchange with Temasek Holding owning a 63% initially and gradually reduced to 54% in 2008. During 1990s, the company follows a more aggressive growth pattern, two subsidiaries were form in 1992, Silk Air to close the gap between its route networks and cater to a lower cost market segment, SIA Engineering is form to increase productivity and pursuit better business opportunity. Globalisation in the 1990s have also prompt the airline to expand overseas, invest in other airline company and forming new subsidiary in other country to provide better support on is airlines. The Asia financial crises at the end of 1990s prompt the airline to review its operation cost again, cutting down on not profitable route. [St James Press, 1999]. Against conventional wisdom, the company have utilized its strong financial resources during financial crisis to make capital investment, spending 300million to renovate cabins of its aircraft. This had benefit the airlines as the price level during the crisis is low and the airlines have more bargaining power over its supplier [Scott, 2008].
Till date, Singapore Airlines group of companies provide passenger and cargo air transportatio