Search

Your search keyword '"Ma, Jiajia"' showing total 445 results
Start Over Author "Ma, Jiajia"
445 results on '"Ma, Jiajia"'

1. Smart-LLaMA: Two-Stage Post-Training of Large Language Models for Smart Contract Vulnerability Detection and Explanation

Author

Yu, Lei, Chen, Shiqi, Yuan, Hang, Wang, Peng, Huang, Zhirong, Zhang, Jingyuan, Shen, Chenjie, Zhang, Fengjun, Yang, Li, and Ma, Jiajia

Subjects
Computer Science - Cryptography and Security, Computer Science - Artificial Intelligence, Computer Science - Software Engineering
Abstract

With the rapid development of blockchain technology, smart contract security has become a critical challenge. Existing smart contract vulnerability detection methods face three main issues: (1) Insufficient quality of datasets, lacking detailed explanations and precise vulnerability locations. (2) Limited adaptability of large language models (LLMs) to the smart contract domain, as most LLMs are pre-trained on general text data but minimal smart contract-specific data. (3) Lack of high-quality explanations for detected vulnerabilities, as existing methods focus solely on detection without clear explanations. These limitations hinder detection performance and make it harder for developers to understand and fix vulnerabilities quickly, potentially leading to severe financial losses. To address these problems, we propose Smart-LLaMA, an advanced detection method based on the LLaMA language model. First, we construct a comprehensive dataset covering four vulnerability types with labels, detailed explanations, and precise vulnerability locations. Second, we introduce Smart Contract-Specific Continual Pre-Training, using raw smart contract data to enable the LLM to learn smart contract syntax and semantics, enhancing their domain adaptability. Furthermore, we propose Explanation-Guided Fine-Tuning, which fine-tunes the LLM using paired vulnerable code and explanations, enabling both vulnerability detection and reasoned explanations. We evaluate explanation quality through LLM and human evaluation, focusing on Correctness, Completeness, and Conciseness. Experimental results show that Smart-LLaMA outperforms state-of-the-art baselines, with average improvements of 6.49% in F1 score and 3.78% in accuracy, while providing reliable explanations.

Published
2024

3. A Novel Attack Missile Guidance Method Considering the Terminal Angle Constraint of the Attack Missile-Target-Defense Missile Game

Author

Pan, Jiaxing, Ma, Jiajia, Huang, Junhua, Sun, Chong, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Tan, Kay Chen, Series Editor, Yan, Liang, editor, and Deng, Yimin, editor

Published
2025
Full Text
View/download PDF

11. Photochemical Dearomative Cycloadditions of Quinolines and Alkenes: Scope and Mechanism Studies.

Author

Guo, Renyu, Adak, Souvik, Bellotti, Peter, Gao, Xinfeng, Smith, W, Le, Sam, Ma, Jiajia, Glorius, Frank, Chen, Shuming, Brown, M, and Houk, Kendall

Subjects
Alkenes, Catalysis, Cycloaddition Reaction, Molecular Structure, Quinolines
Abstract

Photochemical dearomative cycloaddition has emerged as a useful strategy to rapidly generate molecular complexity. Within this context, stereo- and regiocontrolled intermolecular para-cycloadditions are rare. Herein, a method to achieve photochemical cycloaddition of quinolines and alkenes is shown. Emphasis is placed on generating sterically congested products and reaction of highly substituted alkenes and allenes. In addition, the mechanistic details of the process are studied, which revealed a reversible radical addition and a selectivity-determining radical recombination. The regio- and stereochemical outcome of the reaction is also rationalized.

Published
2022

15. Photochemical intermolecular dearomative cycloaddition of bicyclic azaarenes with alkenes

Author

Ma, Jiajia, Chen, Shuming, Bellotti, Peter, Guo, Renyu, Schäfer, Felix, Heusler, Arne, Zhang, Xiaolong, Daniliuc, Constantin, Brown, M Kevin, Houk, Kendall N, and Glorius, Frank

Subjects
Alkenes, Catalysis, Cycloaddition Reaction, Energy Transfer, Hydrocarbons, Aromatic, Molecular Structure, Quinolines, Stereoisomerism, General Science & Technology
Abstract

Dearomative cycloaddition reactions represent an ideal means of converting flat arenes into three-dimensional architectures of increasing interest in medicinal chemistry. Quinolines, isoquinolines, and quinazolines, despite containing latent diene and alkene subunits, are scarcely applied in cycloaddition reactions because of the inherent low reactivity of aromatic systems and selectivity challenges. Here, we disclose an energy transfer-mediated, highly regio- and diastereoselective intermolecular [4 + 2] dearomative cycloaddition reaction of these bicyclic azaarenes with a plethora of electronically diverse alkenes. This approach bypasses the general reactivity and selectivity issues, thereby providing various bridged polycycles that previously have been inaccessible or required elaborate synthetic efforts. Computational studies with density functional theory elucidate the mechanism and origins of the observed regio- and diastereoselectivities.

Published
2021

24. Intermolecular donor–acceptor stacking to suppress triplet exciton diffusion for long-persistent organic room-temperature phosphorescence.

Author

Ma, Jiajia, Dou, Jiawen, Xu, Nuo, Wang, Guo, Duan, Yuai, Liao, Yi, Yi, Yuanping, and Geng, Hua

Subjects
*PHOSPHORESCENCE, *PHOSPHORESCENCE spectroscopy, *PHOSPHORIMETRY, *DENSITY functional theory, *CHARGE transfer, *CRYSTAL surfaces
Abstract

Controlling triplet states is crucial to improve the efficiency and lifetime of organic room temperature phosphorescence (ORTP). Although the intrinsic factors from intramolecular radiative and non-radiative decay have been intensively investigated, the extrinsic factors that affect triplet exciton quenching are rarely reported. Diffusion to the defect sites inside the crystal or at the crystal surface may bring about quenching of triplet exciton. Here, the phosphorescence lifetime is found to have a negative correlation with the triplet exciton diffusion coefficient based on the density functional theory (DFT)/time-dependent density functional theory (TD-DFT) calculations on a series of ORTP materials. For systems with a weak charge transfer (CT) characteristic, close π–π stacking will lead to strong triplet coupling and fast triplet exciton diffusion in most cases, which is detrimental to the phosphorescence lifetime. Notably, for intramolcular donor–acceptor (D–A) type systems with a CT characteristic, intermolecular D–A stacking results in ultra-small triplet coupling, thus contributing to slow triplet diffusion and long phosphorescence lifetime. These findings shed some light on molecular design toward high-efficiency long persistent ORTP. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

35. Research on Nonlinear Inversion of Vegetation Water Content Based on Multiple Ground-Based GPS-IR

Author

Li, Jiyang, Liang, Yueji, Ma, Jiajia, Xie, Sidan, Wen, Zhe, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zhang, Junjie James, Series Editor, Yang, Changfeng, editor, and Xie, Jun, editor

Published
2021
Full Text
View/download PDF

41. Half-Sandwich Ru(II) Complexes Featuring Metal-Centered Chirality: Configurational Stabilization by Ligand Design, Preparation via Kinetic Resolution, and Application in Asymmetric Catalysis

Author

Liang, Hui, Morais, Gabriel N., Chen, Gang, Tang, Wei, Zhao, Jing, Wang, Chuanyong, Houk, K. N., Chen, Shuming, and Ma, Jiajia

Abstract

While it is well established that half-sandwich Ru(II) complexes possess metal-centered chirality, effective strategies to leverage their metal-centered chirality toward asymmetric synthesis have been challenging due to the configurational lability of the metal stereocenters. The metal-centered chirality is typically mediated by enantiopure ligands, which occupy a relatively narrow chemical space compared to their achiral counterparts. We demonstrate that achiral ligands can be used to access chiral-at-ruthenium half-sandwich complexes with exceptionally high configurational stability. Key to success is the introduction of a rigid bidentate ligand with a minimized dihedral angle between the pyridyl and phenolic moieties, which proved effective for preventing racemization. Computational studies revealed the energetic factors contributing to the exceptional configurational stability enabled by the rigid and planar structure of the successful ligand design. These optically active chiral-at-ruthenium complexes incorporating aldehyde moieties were obtained by NHC-catalyzed kinetic resolution with excellent selectivities (s-factor up to >200, ee up to 99%). We further demonstrate that they are highly effective chiral aldehyde catalysts for the asymmetric 1,6-conjugate addition of glycine ester and para-quinone methide.

Published
2025
Full Text
View/download PDF

43. A synchronous retrieval method of vegetation water content and soil moisture based on GNSS-IR and multi-source data fusion.

Author

Ma, Jiajia, Liang, Yueji, Cheng, Bo, Hu, Xinmiao, Ren, Chao, Yang, Mengmeng, Huang, Yibang, Liang, Caiwen, and Guo, Xi

Subjects
*GLOBAL Positioning System, *SOIL moisture, *MULTISENSOR data fusion, *REFLECTOMETRY, *INTERFEROMETRY
Abstract

Vegetation Water Content (VWC) and Soil Moisture (SM) are closely related. To overcome the limitations of the Global Navigation Satellite System Interferometry Reflectometry (GNSS-IR) for point-based monitoring, this research aimed at developing a synchronous retrieval method for VWC and SM by integrating GNSS-IR and multi-source data. The method incorporates band synthesis, optimized modelling, and a Stacking algorithm. The model produced Normalized Microwave Reflectance Index (NMRI) and SM products consistent with MODIS NDVI, LAI, and NASA-USDA SM data in both time and space. The study provides a novel approach for the synchronous retrieval of VWC and SM and facilitates in-depth exploration of their interaction mechanisms. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

49. Late-Stage Saturation of Drug Molecules

Author

Liu, De-Hai, primary, Pflüger, Philipp M., additional, Outlaw, Andrew, additional, Lückemeier, Lukas, additional, Zhang, Fuhao, additional, Regan, Clinton, additional, Rashidi Nodeh, Hamid, additional, Cernak, Tim, additional, Ma, Jiajia, additional, and Glorius, Frank, additional

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results