Lei Chang

dblp:23/875 · DBLP profile ↗
← Back
9ranked-venue papers
6as first author
1since 2021 · last 2025
—ORCID · conflict

Domains — the database's venue-derived domains; a paper can count in several

Databases, data management, data science and information retrieval · 7 · 5 first-author · 1 since 2021Artificial intelligence and machine learning · 4 · 3 first-authorSystems, architecture and hardware · 1

Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.

Databases, data mining, and information retrieval
2 papers
Data mining · 29% Database system architecture and tuning · 22% Distributed and cloud data management · 22%
Computer architecture, parallel and distributed computing, and storage systems
1 paper
Storage systems · 100%

Topics — the 6 heaviest of 9, each with the papers that count most for it

TopicWeightPapersLastEvidence papers
Database system architecture and tuning
massively parallel processing
0.212014
HAWQ: a massively parallel processing SQL engine in hadoop · SIGMOD Conference 2014
Data mining › pattern mining › sequential pattern mining
closed sequential pattern mining
0.112008
SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows · ICDM 2008
Data mining
pattern mining
0.112008
SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows · ICDM 2008
Data mining › pattern mining
sequential pattern mining
0.112008
SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows · ICDM 2008
Data stream processing › continuous query processing
sliding window
0.112008
SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows · ICDM 2008
Data stream processing
stream mining
0.112008
SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows · ICDM 2008

Methods — techniques the papers use, named apart from their topics

UDP-based software interconnect · 0.4
YearPublicationVenuePosition
2025 ChampionNet: a transformer-enhanced neural architecture search framework for athletic performance prediction and training optimization
abstract
Abstract Neural architecture search (NAS) has emerged as a promising approach for automating deep learning model design. However, its application in sports analytics faces unique challenges due to the complex interplay between biomechanical patterns, physiological adaptations, and coaching expertise. Traditional NAS methods need help to effectively capture the multifaceted nature of athletic performance, often failing to integrate qualitative coaching insights with quantitative measurements. We introduce ChampionNet, a framework incorporating NAS and large language models to enhance accuracy in predicting athletic performance and tailoring training regimens. Our approach offers three primary contributions: integrating hyperdimensional embedding to capture fine-grained biomechanical features and physiological parameters with exceptional detail, a structure-preserving graph encoding leverages to maintain crucial spatiotemporal relationships in athletic movements, and the novel comprehensiveness of the training graph that models forward performance prediction and backward physiological adaptation pathways. Our experiments on various sports demonstrate that ChampionNet outperforms other models by 2.5% in accuracy and over 61.9% in computational cost. Further insights illustrate the framework's performance with complex patterns and multi-modal data, especially for sports with advanced biomechanical needs. These findings support ChampionNet's effectiveness as an integrative athletic performance optimization solution, highlighting the need for automated architecture search tailored to sports.
Lei Chang, Shalli Rani, Muhammad Azeem Akbar
Discov. Comput.1
2017 An evaluation of analytical queries on CPUs and coupled GPUs
abstract
Summary Recently, the mainstream hardware vendors such as Intel and AMD have made significant efforts to integrate the central processing unit (CPU) and the graphics processing unit (GPU) into a single chip, which forms a coupled CPU‐GPU architecture. Data transfer between the CPU and the GPU through a Peripheral Component Interconnect Express bus is eliminated on this architecture, which provides new opportunities for database community to optimize query processing. Because of the lack of comprehensive evaluation of database systems on coupled CPU‐GPU platforms, it is difficult for academic and industry researchers to make appropriate decisions on improvement and optimization directions. In this paper, we conduct an extensive experimental study to evaluate an online analytical processing system on Intel and AMD machines. The performance difference is measured and analyzed when executing queries on integrated GPUs and multicore CPUs. The impacts of various parameters, data sizes, and optimization techniques on performance are also investigated. The results provide preliminary insights into database query and operator behaviors on state‐of‐the‐art coupled CPU‐GPU architectures.
Hua Luan, Lei Chang
Concurr. Comput. Pract. Exp.2
2014 HAWQ: a massively parallel processing SQL engine in hadoop
abstract
HAWQ, developed at Pivotal, is a massively parallel processing SQL engine sitting on top of HDFS. As a hybrid of MPP database and Hadoop, it inherits the merits from both parties. It adopts a layered architecture and relies on the distributed file system for data replication and fault tolerance. In addition, it is standard SQL compliant, and unlike other SQL engines on Hadoop, it is fully transactional. This paper presents the novel design of HAWQ, including query processing, the scalable software interconnect based on UDP protocol, transaction management, fault tolerance, read optimized storage, the extensible framework for supporting various popular Hadoop based data stores and formats, and various optimization choices we considered to enhance the query performance. The extensive performance study shows that HAWQ is about 40x faster than Stinger, which is reported 35x-45x faster than the original Hive.
Lei Chang, Zhanwei Wang, Lirong Jian, Alon Goldshuv, Luke Lonergan, Jeffrey Cohen, Caleb Welton, Gavin Sherry, Milind Bhandarkar
SIGMOD Conference1
2012 A New Two-Layer Topology for Data Center Network
abstract
In the cloud computing era, the goal of data center network is not only to interconnect a large number of servers, but also to provide low latency and high bandwidth. A new 2-layer architecture, C-tree, is proposed for cloud computing in this paper. It is a flat topology, in which the horizontal traffic's latency is obviously lower than in traditional three-layer architectures. Also, C-tree can provide high bisection bandwidth which is important for bandwidth-intensive applications. We analyze C-tree theoretically and compare it with other architectures in scalability, accommodation capability, network diameter, bisection bandwidth, path diversity and regularity. We have developed a load balancing routing mechanism to balance the traffic on the parallel links. A network simulation platform is set up to verify the performance of C-tree.
Lei Chang, Huaxi Gu, Kun Wang 0001, Ruoyan Liu
PDCAT1
2009 Aggregation Models for People Finding in Enterprise Corpora
Lei Chang, Jianqing Ma, YiPing Zhong
KSEM2
2009 Efficient algorithms for incremental maintenance of closed sequential patterns in large databases
Lei Chang, Tengjiao Wang 0003, Dongqing Yang, Hua Luan, Shiwei Tang
Data Knowl. Eng.1
2008 SeqStream: Mining Closed Sequential Patterns over Stream Sliding Windows
abstract
Previous studies have shown mining closed patterns provides more benefits than mining the complete set of frequent patterns, since closed pattern mining leads to more compact results and more efficient algorithms. It is quite useful in a data stream environment where memory and computation power are major concerns. This paper studies the problem of mining closed sequential patterns over data stream sliding windows. A synopsis structure IST (Inverse Closed Sequence Tree) is designed to keep inverse closed sequential patterns in current window. An efficient algorithm SeqStream is developed to mine closed sequential patterns in stream windows incrementally, and various novel strategies are adopted in SeqStream to prune search space aggressively. Extensive experiments on both real and synthetic data sets show that SeqStream outperforms PrefixSpan, CloSpan and BIDE by a factor of about one to two orders of magnitude.
Lei Chang, Tengjiao Wang 0003, Dongqing Yang, Hua Luan
ICDM1
2008 BOAI: Fast Alternating Decision Tree Induction Based on Bottom-Up Evaluation
Bishan Yang, Tengjiao Wang 0003, Dongqing Yang, Lei Chang
PAKDD4
2006 Mining Compressed Sequential Patterns
Lei Chang, Dongqing Yang, Shiwei Tang, Tengjiao Wang 0003
ADMA1