The application period is year around in batches and must be kept a tab on while applying. Check out the details below copied from the NTU website. I have posted the link below of the website:
The
 NTU-India Connect Research Internship Programme is a university-wide 
short-term research programme lasting for 2 to 6 months. It is initiated
 to enable undergraduate and graduate students from Indian Universities 
and Institutes of higher learning to pursue research at NTU. 
Participants of this programme will work under the supervision of NTU 
faculty, develop a strong research interest and expertise in a given 
research field, experience multicultural living, gain a network of 
friends and a better understanding of Singapore. 
 
 Eligible
 students may be given an allowance, and are expected to fulfil a 
minimum of 8 weeks research attachment comprising research project work 
at NTU. All participants will receive a certificate issued by NTU upon 
completion of the programme.
Eligibility Criteria
- Open to Pre-final year graduate / undergraduates who have not studied in NTU Singapore previously.
- Applicants must possess good academic track records. 
- Applicants must be a student perusing his / her studies in an Indian University / Institution. 
Application Procedure
Students may select the projects listed here and submit the online application.
 Please email all the necessary supporting documents listed in the 
checklist with three names of the faculty whom you would like to work 
with, to Prof. B.V.R. Chowdari, Senior Executive Director, President's 
Office at indiaconnect@ntu.edu.sg Those
 shortlisted candidates will be referred to suggested faculty for their 
consent and if agreed internship offer will be made. If we do not 
receive a complete set of application and supporting documents, your 
application will not be considered. 
Those
 students who intend to have the internship for longer period (> 
2months) must have a supervisor at the home institution and the 
supervisors at both institutions must come to a common understanding 
about the research project before the application being considered. A 
recommendation letter from International Relations office is require. 
Allowance
The grant is tenable only for the duration of the programme at NTU. Each grant may cover the following in full or partial:
- One-time travel support to the extent of SGD300.
- A single / double occupancy accommodation inside or outside the University (subject to availability).
- SDG300
 per month (paid out on a monthly basis). Should your stay either be 
less or more than a month the amount will be proportional.
- Reimbursement
 of miscellaneous fees such as TEP Application, Matriculation Card, IT 
Facilities Fee, Registration Fee, University Copyright Fee and Group 
Hospitalisation & Surgical Insurance (GHSI) Scheme with the 
final financial allowance pay-out.
 
Accommodation
Accommodation on campus may be provided within the programme dates 
indicated. Accommodation is subject to the availability for any period 
outside the programme date indicated. Those students who cannot get 
accommodation on campus may source the same through the Off-Campus Accommodation System (OCAS). Information on renting accommodation off-campus can be found here.   
Training Employment Pass (TEP)
All
 international students are required to obtain a valid Training 
Employment Pass issued by Ministry of Manpower (MOM) in order to 
participate in NTU-India Connect Programme.
Here is the link to the website: NTU-India Connect