hi,

see many of the polytechnic or diploma college is affiliated by AICTE, now your college is affiliated by UGC , which is also satisfactory, however it also depends on the organization or recruitment criteria , if it mentioned that aicte approval is necessary then you may not eligible to apply, now coming to central government jobs, I have checked the eligibility criteria for ssc je for diploma holders, where it requires candidates must pass diploma course from a recognized institute, so since there is no mention of aicte , you may surely apply.