Okay, this is what I think. For 1, it's a usual academic project. Nonetheless, I am going to give it a shot:
1. Look up theory on the size of organization, growth, etc. Primary factors influencing size - common sense tells me are Market, ability to raise capital, short-term long-term investment, desire of the organization to grow, ability of management (a small shopkeeper may not be able to manage a chain of supermarkets even if he gets that kind of capital - actually if you can study the retail market, it will help you understand), long-term goals, manpower (Currently, it has been predicted that in the next year alone the top 6 IT companies will hire 150,000 IT engineers, and the total output of IT engineers in India is 125,000 - so lack of skilled manpower at an affordable cost can also be a reason for not being able to expand), technology, geography (small percentage) (say you want to create electricity from the sun - lucrative market - but technology does not exist that can help you do it on a large scale / say your country is very small - you would have to manufacture it elsewhere & hence Supply chain management becomes important) & finally political environment (see guru - The Parsi community had the license & no one wanted to entertain the outsider Gujarati) & economics - If expanding costs more money than it can yield for - it's still a meaningless business. i.e., my marginal cost and marginal cost must at least break even - (see the law of price fixation in economics).
I have told you this off the cuff - speak to the higher-level managers of your organization & ask them regarding what are their thoughts.
2. Personnel functions handle the manpower - actually here you can sing the entire permanent or temporary staff raga & how HR function plays a key role in managing costs.
3. For the role of HR - you will have to talk about how HR will arrive at the number required to support this expansion or contraction & how it plans to add or reduce manpower with the least impact. HR to person ratio, communication of expansion or contraction, What culture would it like to have & how to create that culture - Also HR could work with the technology people & look at what all can be automated to reduce employee costs, time & create a more effective manpower time usage.
4. HR will also play a key role in organizing - i.e., org structure required to support the size of the organization - All hiring must be according to the hiring plan & org structure.
5. For factors affecting HR plan - again budget, manpower sanctioned, HR staff, quality of HR staff, Industry & very importantly the quality of the people at the top - a Marwadi company owner vis-a-vis an MNC culture even if it's of the same size.
I hope this helped.
Regards,
A