Contact Support
Model Benchmarking

IR Model Comparison — 2024

Detailed comparison of all 6 retrieval models evaluated on the SPIAL China Visa FAQ dataset (762 questions, 118 unique answers).

Model Prec@5 MRR NDCG@10 Inference Memory Type
CWS-TFIDF
★ Proposed · This Thesis
 92.4% 0.891 0.874 ~0.9ms ~1.2MB Sparse+Sem
all-MiniLM-L6-v2
Sentence-Transformers · 2024
 90.1% 0.869 0.851 ~28ms ~85MB Dense Neural
SPLADE-V3
NAVER LABS · 2024
 89.7% 0.862 0.843 ~45ms ~120MB Sparse Neural
DistilBERT
HuggingFace · 2019
 88.3% 0.841 0.829 ~186ms ~250MB Dense Neural
Word2Vec
Google · 2013
 84.7% 0.812 0.798 ~14ms ~30MB Dense Static
TF-IDF
Classical IR · Baseline
 80.1% 0.771 0.754 ~0.6ms ~0.8MB Sparse Classic
Model Profiles

Architecture & Characteristics

CWS-TFIDF
★ Proposed · 2024 Thesis
Sparse+SemanticDomain-awareNo GPU needed
Precision@592.4%
Params0 (non-neural)
Index size~1.2 MB
Extends classic TF-IDF with a contextual semantic boost layer. Domain-specific terms receive a 1.1× weight multiplier derived from Word2Vec co-occurrence vocabulary. Combines the speed of sparse retrieval with semantic awareness — achieving best-in-class accuracy without neural overhead.
all-MiniLM-L6-v2
Sentence-Transformers · 2024
Dense Neural22M ParamsBi-encoder
Precision@590.1%
Params22.7M
Model size~85 MB
A compact, fine-tuned BERT model distilled for sentence similarity. Uses a 6-layer transformer to produce 384-dim sentence embeddings. Strong semantic understanding, fast inference for neural models, widely used in production retrieval systems. Requires GPU for real-time at scale.
SPLADE-V3
NAVER LABS Europe · 2024
Sparse NeuralBERT-basedVocab expansion
Precision@589.7%
Params~110M
Model size~120 MB
State-of-the-art sparse neural retrieval model using BERT with regularization to produce interpretable sparse vectors over the vocabulary. Combines the efficiency of sparse inverted indexes with learned BERT representations. Achieves near-dense-model quality with inverted index speed.
DistilBERT
HuggingFace · 2019
Dense Neural66M Params6-layer BERT
Precision@588.3%
Params66M
Model size~250 MB
Distilled BERT model with 40% fewer parameters, 60% faster inference, retaining 97% of BERT performance. Used here for n-gram based similarity on corpus documents. Higher memory footprint vs sparse methods. Slowest model in this benchmark.
Word2Vec
Google · Mikolov et al. 2013
Dense Static64-dim embedSkip-gram
Precision@584.7%
Embed dim64
Memory~30 MB
Foundational static word embedding model. Average word vectors used for document representation. Lacks contextual understanding — same word has same vector regardless of context. Strong baseline but outperformed by all contextual models. Good speed-accuracy tradeoff.
TF-IDF
Classical IR · Baseline
Sparse ClassicNo MLFastest
Precision@580.1%
Params0 (non-neural)
Memory~0.8 MB
Classic term frequency-inverse document frequency retrieval. Computes sparse vector for each document; cosine similarity for ranking. Lowest memory and fastest inference. No semantic understanding — suffers from vocabulary mismatch. Strong explainability. The CWS-TFIDF proposed method extends this baseline.
Document Preparation

Visa Application Checklists

Interactive checklists for each visa type. Check off items as you gather them.

✦ X1 visa is for study programs longer than 180 days. Convert to residence permit within 30 days of arrival.
✦ X2 visa is for study programs 180 days or less. No residence permit conversion required.
✦ Z visa requires employer sponsorship. Convert to work residence permit within 30 days of arrival.
✦ L (tourist) visa is for sightseeing and visiting. Working or studying on L visa is illegal.
✦ M (business) visa is for commercial activities only. Not for employment or study.
International Student Support

University Resources & Official Links

Essential resources for international students navigating China's visa system and university life.

🌐
Official Portal
China Visa Application
Official online visa application system for all Chinese visa types. Complete forms, upload photos, track status.
visaforchina.cn →
🏛️
Government
Ministry of Foreign Affairs
China MFA official visa policies, bilateral agreements, visa-free access lists, and policy announcements.
mfa.gov.cn →
🛂
Immigration
National Immigration Admin
Exit-entry policies, residence permits, temporary registration, and immigration bureau locations nationwide.
nia.gov.cn →
🎓
Education
Ministry of Education
JW201/JW202 forms, CSC scholarships, university accreditation, and study in China programs.
moe.gov.cn →
🏅
Scholarships
CSC Scholarship Portal
Chinese Government Scholarship applications, eligibility criteria, program listings, and JW202 form requests.
campuschina.org →
🏢
Embassy Finder
Chinese Embassies Worldwide
Find your nearest Chinese embassy or CVASC, book appointments, check country-specific document requirements.
fmprc.gov.cn →
🏥
Medical
International Health Centers
Designated International Travel Health Care Centers for required medical examinations. Find the nearest authorized center.
chinaport.gov.cn →
🚔
Registration
PSB Exit-Entry Bureau
Residence permit applications, extensions, police registration, and temporary residence certificates at local PSB offices.
Local PSB → Find yours
📦
Track Status
Visa Application Tracker
Track your visa application status online using your application reference number and passport details.
visaforchina.cn/track →
💼
Work Permits
HRSS Work Permit System
Foreign work permit applications, notifications, renewals, and cancellations through the HR ministry system.
fld.mohrss.gov.cn →
🏔️
Special Permits
Tibet Travel Permit
Tibet Tourism Bureau permits required in addition to China visa. Must book through a licensed Tibetan travel agency.
tibet.cn →
🇧🇩
Bangladesh
Chinese Embassy Dhaka
Plot 2 & 4, Road 5, Baridhara, Dhaka-1212. CVASC for visa applications, appointments, and document verification.
bd.china-embassy.gov.cn →
Application Timeline

Student Visa Timeline Guide

Step-by-step timeline for international students applying to Chinese universities. Times are estimates based on typical application cycles.

6–12 Months Before Departure
Research & Apply to Universities
Research Chinese universities, program requirements, tuition fees. Submit online applications via university portals or campuschina.org for CSC scholarships.
Action Required
4–6 Months Before Departure
Receive Admission Letter + JW Form
University issues Admission Letter and JW201/JW202 form. CSC scholarship students receive JW202. Self-funded students receive JW201. These are mandatory for visa application.
University Action
3–4 Months Before Departure
Complete Medical Examination
Undergo physical examination at an authorized hospital in your home country. Examination valid for 6 months. Includes blood tests, chest X-ray, ECG, and general physical assessment.
Time-sensitive
2–3 Months Before Departure
Gather All Documents & Book Appointment
Compile all visa documents (passport, photos, JW form, admission letter, bank statement, health certificate, police clearance). Book appointment at visaforchina.cn or local CVASC.
Preparation
6–8 Weeks Before Departure
Submit Visa Application
Submit all documents at the Chinese Embassy or CVASC. Standard processing: 4–7 working days. Express: 2–3 days. Urgent: 1–2 days. Track application status online.
Critical Step
4–6 Weeks Before Departure
Collect Passport + Plan Travel
Collect passport with visa stamp. Book flights ensuring arrival during semester registration period. Book initial accommodation (university dorm or private). Purchase travel and health insurance.
Logistics
Upon Arrival in China
Register at Police Station (24 Hours)
Register at local police station (PSB) within 24 hours of arrival at private accommodation. Dormitory students are registered by the university. Receive Temporary Residence Registration Certificate.
⚠ Mandatory
Within 30 Days of Arrival
Convert X1 Visa → Residence Permit
Visit local PSB Exit-Entry Administration Bureau with passport, visa, university enrollment certificate, accommodation registration, health insurance, and photos. Processing: 5–15 working days. Fee: ~CNY 400.
⚠ Deadline
Every Year (30 Days Before Expiry)
Renew Residence Permit
Apply for annual renewal at the PSB with updated enrollment certificate, new accommodation registration, and health insurance renewal. Never wait until permit expires — penalties are severe (CNY 500/day).
Annual
Key Deadlines
Police Registration24 hours
X1 → Residence Permit30 days
Apply for Renewal30 days early
Health Certificate Valid6 months
Bank Statement Range3–6 months
Overstay FineCNY 500/day
Max Overstay FineCNY 10,000
Processing Times
Standard Visa4–7 days
Express Visa2–3 days
Urgent Visa1–2 days
Residence Permit5–15 days
Work Permit5–15 days
Permanent Residence6–12 months
⚠ Common Mistakes
• Forgetting police registration within 24 hrs
• Not converting X1 visa within 30 days
• Missing residence permit renewal deadline
• Expired health certificate at submission
• Working on student visa without permission
• Switching universities without updating permit