Michael Hitchens

128 papers A 5B 15C 17Misc 11Journal 43Unranked 37

Year	Rank	Type	Title / Venue / Authors
2024	J	`jnl`	A Blockchain-Based Approach for Parametric Insurance Under Multiple Sources of Truth. IEEE Trans. Serv. Comput. Tahiry M. Rabehaja, Shantanu Pal, Ambrose Hill, Michael Hitchens
2024	B	`conf`	Experiential Learning or Direct Training: Fostering Ethical Cybersecurity Decision-Making via Serious Games. PERSUASIVE Bakhtiar Sadeghi, Deborah Richards, Paul Formosa, Michael Hitchens
2024	—	`conf`	Exploring the Impact of Tailored Game Content on Ethical Decision-Making Competence in Cybersecurity. ACIS Bakhtiar Sadeghi, Deborah Richards, Paul Formosa, Michael Hitchens
2024	—	`conf`	Poster: Zero Trust Driven Architecture for Blockchain-Based Access Control Delegation. SIGCOMM (Posters and Demos) Rahma Mukta, Shantanu Pal, Michael Hitchens, Hye-Young Paik, Salil S. Kanhere
2023	C	`conf`	A Blockchain-Based Interoperable Architecture for IoT with Selective Disclosure of Information. PRDC Rahma Mukta, Shantanu Pal, Shailesh Mishra, Hye-Young Paik, Salil S. Kanhere, Michael Hitchens
2023	J	`jnl`	A trust-aware openflow switching framework for software defined networks (SDN). Comput. Networks Kallol Krishna Karmakar, Vijay Varadharajan, Michael Hitchens, Uday Kiran Tupakula, Prajna Sariputra
2023	J	`jnl`	Trans* and gender diverse players: Avatars and gender-alignment. Entertain. Comput. Kayson Whitehouse, Michael Hitchens, Nicole Matthews
2022	C	`conf`	An Exploitation Ecosystem Model for Fan-based Labour in the Games Industry. DiGRA Christopher McCutcheon, Michael Hitchens, Mitchell W. McEwan
2022	C	`conf`	Design of a Serious Game for Cybersecurity Ethics Training. DiGRA Malcolm Ryan, Mitchell W. McEwan, Vedant Sansare, Paul Formosa, Deborah Richards, Michael Hitchens
2022	—	`conf`	How to increase ethical awareness in cybersecurity decision-making. ACIS Bakhtiar Sadeghi, Deborah Richards, Paul Formosa, Mitchell W. McEwan, Michael Hitchens
2022	J	`jnl`	SDPM: A Secure Smart Device Provisioning and Monitoring Service Architecture for Smart Network Infrastructure. IEEE Internet Things J. Kallol Krishna Karmakar, Vijay Varadharajan, Pete Speirs, Michael Hitchens, Aron Robertson
2022	J	`jnl`	Toward a Trust Aware Network Slice-Based Service Provision in Virtualized Infrastructures. IEEE Trans. Netw. Serv. Manag. Vijay Varadharajan, Kallol Krishna Karmakar, Uday Kiran Tupakula, Michael Hitchens
2022	B	`conf`	VeriBlock: A Blockchain-Based Verifiable Trust Management Architecture with Provable Interactions. ICCCN Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2022	J	`jnl`	VeriBlock: A Blockchain-Based Verifiable Trust Management Architecture with Provable Interactions. CoRR Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2021	J	`jnl`	A Blockchain-Based Trust Management Framework with Verifiable Interactions. CoRR Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2021	J	`jnl`	A Graph-Based Fault-Tolerant Approach to Modeling QoS for IoT-Based Surveillance Applications. IEEE Internet Things J. Diya Thomas, Mehmet A. Orgun, Michael Hitchens, Rajan Shankaran, Subhas Chandra Mukhopadhyay, Wei Ni
2021	J	`jnl`	A blockchain-based trust management framework with verifiable interactions. Comput. Networks Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2021	—	`conf`	Controlling Resource Allocation using Blockchain-Based Delegation. GLOBECOM (Workshops) Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2021	J	`jnl`	Controlling Resource Allocation using Blockchain-Based Delegation. CoRR Shantanu Pal, Ambrose Hill, Tahiry M. Rabehaja, Michael Hitchens
2021	J	`jnl`	QoS-Aware Energy Management and Node Scheduling Schemes for Sensor Network-Based Surveillance Applications. IEEE Access Diya Thomas, Rajan Shankaran, Quan Z. Sheng, Mehmet A. Orgun, Michael Hitchens, Mehedi Masud, Wei Ni, Subhas Chandra Mukhopadhyay, Md. Jalil Piran
2020	J	`jnl`	Design for Empowerment: Empowering Sri Lankan Farmers through Mobile-based Information System. Commun. Assoc. Inf. Syst. Tamara Ginige, Deborah Richards, Athula Ginige, Michael Hitchens
2020	J	`jnl`	On the Design of a Flexible Delegation Model for the Internet of Things Using Blockchain. IEEE Trans. Ind. Informatics Shantanu Pal, Tahiry M. Rabehaja, Michael Hitchens, Vijay Varadharajan, Ambrose Hill
2020	J	`jnl`	On the Integration of Blockchain to the Internet of Things for Enabling Access Right Delegation. IEEE Internet Things J. Shantanu Pal, Tahiry M. Rabehaja, Ambrose Hill, Michael Hitchens, Vijay Varadharajan
2020	J	`jnl`	Security Requirements for the Internet of Things: A Systematic Approach. Sensors Shantanu Pal, Michael Hitchens, Tahiry M. Rabehaja, Subhas Mukhopadhyay
2020	B	`conf`	Towards a Dynamic Policy Enhanced Integrated Security Architecture for SDN Infrastructure. NOMS Kallol Krishna Karmakar, Vijay Varadharajan, Udaya Kiran Tupakula, Michael Hitchens
2020	J	`jnl`	Towards a Trust Aware Network Slice based End to End Services for Virtualised Infrastructures. CoRR Vijay Varadharajan, Kallol Krishna Karmakar, Udaya Kiran Tupakula, Michael Hitchens
2019	J	`jnl`	A Policy-Based Security Architecture for Software-Defined Networks. IEEE Trans. Inf. Forensics Secur. Vijay Varadharajan, Kallol Krishna Karmakar, Udaya Kiran Tupakula, Michael Hitchens
2019	J	`jnl`	Design and implementation of a secure and flexible access-right delegation for resource constrained environments. Future Gener. Comput. Syst. Tahiry M. Rabehaja, Shantanu Pal, Michael Hitchens
2019	J	`jnl`	Policy-based access control for constrained healthcare resources in the context of the Internet of Things. J. Netw. Comput. Appl. Shantanu Pal, Michael Hitchens, Vijay Varadharajan, Tahiry M. Rabehaja
2019	—	`conf`	Teaching user centered conceptual design using cross-cultural personas and peer reviews for a large cohort of students. ICSE (SEET) Farshid Anvari, Deborah Richards, Michael Hitchens, Hien Minh Thi Tran
2019	—	`conf`	Towards a method for creating personas with knowledge and cognitive process for user centered design of a learning application. CHASE@ICSE Farshid Anvari, Hien Minh Thi Tran, Deborah Richards, Michael Hitchens
2019	A	`conf`	Towards the Design of a Trust Management Framework for the Internet of Things. ICST Shantanu Pal, Michael Hitchens, Vijay Varadharajan
2018	J	`jnl`	A Policy based Security Architecture for Software Defined Networks. CoRR Vijay Varadharajan, Kallol Krishna Karmakar, Udaya Kiran Tupakula, Michael Hitchens
2018	J	`jnl`	A gamification design for the classroom. Interact. Technol. Smart Educ. Michael Hitchens, Rowan Tulloch
2018	J	`jnl`	Fine-Grained Access Control for Smart Healthcare Systems in the Internet of Things. EAI Endorsed Trans. Ind. Networks Intell. Syst. Shantanu Pal, Michael Hitchens, Vijay Varadharajan, Tahiry M. Rabehaja
2018	C	`conf`	Incremental Acquisition of Values to Deal with Cybersecurity Ethical Dilemmas. PKAW Deborah Richards, Virginia Dignum, Malcolm Ryan, Michael Hitchens
2018	A	`conf`	Modeling Identity for the Internet of Things: Survey, Classification and Trends. ICST Shantanu Pal, Michael Hitchens, Vijay Varadharajan
2018	—	`conf`	Player retention in league of legends: a study using survival analysis. ACSW Simon Demediuk, Alexandra Murrin, David W. Bulger, Michael Hitchens, Anders Drachen, William L. Raffe, Marco Tamassia
2018	C	`conf`	Policy-Based Access Control for Constrained Healthcare Resources. WOWMOM Shantanu Pal, Michael Hitchens, Vijay Varadharajan, Tahiry M. Rabehaja
2017	J	`jnl`	An empirical investigation of the influence of persona with personality traits on conceptual design. J. Syst. Softw. Farshid Anvari, Deborah Richards, Michael Hitchens, Muhammad Ali Babar, Hien Minh Thi Tran, Peter Busch
2017	C	`conf`	On Design of A Fine-Grained Access Control Architecture for Securing IoT-Enabled Smart Healthcare Systems. MobiQuitous Shantanu Pal, Michael Hitchens, Vijay Varadharajan, Tahiry M. Rabehaja
2017	A	`conf`	On the design of security mechanisms for the Internet of Things. ICST Shantanu Pal, Michael Hitchens, Vijay Varadharajan
2017	B	`conf`	Towards a Secure Access Control Architecture for the Internet of Things. LCN Shantanu Pal, Michael Hitchens, Vijay Varadharajan
2017	C	`conf`	eSport vs irlSport. ACE Christopher McCutcheon, Michael Hitchens, Anders Drachen
2016	Misc	`conf`	Policy based security architecture for software defined networks. SAC Kallol Krishna Karmakar, Vijay Varadharajan, Udaya Kiran Tupakula, Michael Hitchens
2016	—	`conf`	Predicting player churn in destiny: A Hidden Markov models approach to predicting player departure in a major online game. CIG Marco Tamassia, William L. Raffe, Rafet Sifa, Anders Drachen, Fabio Zambetta, Michael Hitchens
2016	J	`jnl`	The relationship between character identification and flow state within video games. Comput. Hum. Behav. Alistair Raymond Bryce Soutter, Michael Hitchens
2015	B	`conf`	Cross-Domain Attribute Conversion for Authentication and Authorization. ARES Stefan Thaler, Jerry den Hartog, Dhouha Ayed, Dieter Sommer, Michael Hitchens
2015	—	`conf`	Effectiveness of Persona with Personality Traits on Conceptual Design. ICSE (2) Farshid Anvari, Deborah Richards, Michael Hitchens, Muhammad Ali Babar
2015	J	`jnl`	Generic constructions for role-based encryption. Int. J. Inf. Sec. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2015	C	`conf`	Provenance Based Classification Access Policy System Based on Encrypted Search for Cloud Data Storage. ISC Xinyu Fan, Vijay Varadharajan, Michael Hitchens
2015	J	`jnl`	Trust Enhanced Cryptographic Role-Based Access Control for Secure Cloud Data Storage. IEEE Trans. Inf. Forensics Secur. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2014	J	`jnl`	Antivirus security: naked during updates. Softw. Pract. Exp. Byungho Min, Vijay Varadharajan, Udaya Kiran Tupakula, Michael Hitchens
2014	C	`conf`	Cultivation Planning Application to Enhance Decision Making among Sri Lankan Farmers. PKAW Tamara Ginige, Deborah Richards, Michael Hitchens
2014	J	`jnl`	Reality and Terror, the First-Person Shooter in Current Day Settings. Games Cult. Michael Hitchens, Bronwin Patrickson, Sherman Young
2014	J	`jnl`	Secure administration of cryptographic role-based access control for large-scale cloud storage systems. J. Comput. Syst. Sci. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2014	Misc	`conf`	Towards Quantifying Player's Involvement in 3D Games Based-on Player Types. IE Nader Hanna, Deborah Richards, Michael Hitchens, Michael J. Jacobson
2013	—	`conf`	A Trust Management Framework for Secure Cloud Data Storage Using Cryptographic Role-Based Access Control. ICETE (Selected Papers) Lan Zhou, Vijay Varadharajan, Michael Hitchens
2013	J	`jnl`	Achieving Secure Role-Based Access Control on Encrypted Data in Cloud Storage. IEEE Trans. Inf. Forensics Secur. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2013	B	`conf`	Evaluating the Impact of the Human-Agent Teamwork Communication Model (HAT-CoM) on the Development of a Shared Mental Model. PRIMA Nader Hanna, Deborah Richards, Michael Hitchens
2013	Misc	`conf`	Form over function: the use of Lovecraftian elements in World of Warcraft. IE Michael Hitchens, Adam W. Ruch
2013	—	`conf`	Integrating Trust with Cryptographic Role-Based Access Control for Secure Cloud Data Storage. TrustCom/ISPA/IUCC Lan Zhou, Vijay Varadharajan, Michael Hitchens
2013	C	`conf`	Trust-based Secure Cloud Data Storage with Cryptographic Role-based Access Control. SECRYPT Lan Zhou, Vijay Varadharajan, Michael Hitchens
2012	J	`jnl`	A flexible cryptographic approach for secure data storage in the cloud using role-based access control. Int. J. Cloud Comput. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2012	Misc	`conf`	A novel agent based control scheme for RTS games. IE Matt Cabanag, Deborah Richards, Michael Hitchens
2012	Misc	`conf`	An investigation of Vladimir Propp's 31 functions and 8 broad character types and how they apply to the analysis of video games. IE Andrew Brusentsev, Michael Hitchens, Deborah Richards
2012	Misc	`conf`	An investigation of player to player character identification via personal pronouns. IE Michael Hitchens, Anders Drachen, Deborah Richards
2012	B	`conf`	Trusted Administration of Large-Scale Cryptographic Role-Based Access Control Systems. TrustCom Lan Zhou, Vijay Varadharajan, Michael Hitchens
2011	J	`jnl`	A Survey of First-person Shooters and their Avatars. Game Stud. Michael Hitchens
2011	J	`jnl`	Enforcing Role-Based Access Control for Secure Data Storage in the Cloud. Comput. J. Lan Zhou, Vijay Varadharajan, Michael Hitchens
2010	C	`conf`	Analysis of Property Based Attestation in Trusted Platforms. EUC Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens
2009	C	`conf`	ALOPA: Authorization Logic for Property Attestation in Trusted Platforms. ATC Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens
2009	—	`conf`	Context-Aware Trust Management for Peer-to-Peer Mobile Ad-Hoc Networks. COMPSAC (2) Rajan Shankaran, Vijay Varadharajan, Mehmet A. Orgun, Michael Hitchens
2009	Misc	`conf`	Critical Issues in Trust Management for Mobile Ad-Hoc Networks. IRI Rajan Shankaran, Vijay Varadharajan, Mehmet A. Orgun, Michael Hitchens
2009	J	`jnl`	Game Time: Modeling and Analyzing Time in Multiplayer and Massively Multiplayer Games. Games Cult. Anders Tychsen, Michael Hitchens
2009	—	`conf`	Modeling the Story Facilitation of Game Masters in Multi-Player Role-Playing Games. AAAI Spring Symposium: Intelligent Narrative Technologies II Anders Drachen, Michael Hitchens, Ruth Aylett, Sandy Louchart
2009	B	`conf`	Property Based Attestation and Trusted Computing: Analysis and Challenges. NSS Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens, Eimear Gallery
2009	—	`conf`	Role-Playing Games: The State of Knowledge [Panel Abstracts]. DiGRA Conference Anders Drachen, Marinka Copier, Markus Montola, Mirjam P. Eladhari, Michael Hitchens, Jaakko Stenros
2009	—	`conf`	The Personal Experience of Narratives in Role-Playing Games. AAAI Spring Symposium: Intelligent Narrative Technologies II Michael Hitchens, Anders Drachen
2009	—	`conf`	Towards Data-Driven Drama Management: Issues in Data Collection and Annotation. DiGRA Conference Anders Drachen, Michael Hitchens, Arnav Jhala, Georgios N. Yannakakis
2008	J	`jnl`	Character play: the use of game characters in multi-player role-playing games across platforms. Comput. Entertain. Anders Tychsen, Michael Hitchens, Thea Brolund
2008	—	`conf`	Managing emergent character-based narrative. INTETAIN Ruth Aylett, Sandy Louchart, Anders Tychsen, Michael Hitchens, Rui Figueiredo, Carlos Delgado-Mata
2008	—	`conf`	Motivations for play in computer role-playing games. Future Play Anders Tychsen, Michael Hitchens, Thea Brolund
2008	B	`conf`	On the Applicability of Trusted Computing in Distributed Authorization Using Web Services. DBSec Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens, Saurabh Arora
2008	C	`conf`	Verbal Communication of Story Facilitators in Multi-player Role-Playing Games. ICIDS Anders Tychsen, Thea Brolund, Michael Hitchens
2007	—	`conf`	Cross-format analysis of the gaming experience in multi-player role-playing games. DiGRA Conference Anders Tychsen, Ken Newman, Thea Brolund, Michael Hitchens
2007	J	`jnl`	Group play: determining factors on the gaming experience in multiplayer role-playing games. Comput. Entertain. Anders Tychsen, Michael Hitchens, Thea Brolund, Doris McIlwain, Manolya Kavakli
2007	—	`conf`	Player-Character Dynamics in Multi-Player Role Playing Games. DiGRA Conference Anders Tychsen, Doris McIlwain, Thea Brolund, Michael Hitchens
2007	C	`conf`	Trust Management and Negotiation for Attestation in Trusted Platforms Using Web Services. PDCAT Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens
2007	—	`conf`	Trust management for trusted computing platforms in web services. STC Aarthi Nagarajan, Vijay Varadharajan, Michael Hitchens
2006	—	`conf`	Communication in Multi-player Role Playing Games - The Effect of Medium. TIDSE Anders Tychsen, Jonas Heide Smith, Michael Hitchens, Susana Pajares Tosca
2006	—	`conf`	Ghost Worlds - Time and Consequence in MMORPGs. TIDSE Anders Tychsen, Michael Hitchens
2006	J	`jnl`	Live Action Role-Playing Games: Control, Communication, Storytelling, and MMORPG Similarities. Games Cult. Anders Tychsen, Michael Hitchens, Thea Brolund, Manolya Kavakli
2005	—	`conf`	A Trust based Access Control Framework for P2P File-Sharing Systems. HICSS Huu Tran, Michael Hitchens, Vijay Varadharajan, Paul Andrew Watters
2005	—	`conf`	Analysis of Existing Authorization Models and Requirements for Design of Authorization Framework for the Service Oriented Architecture. ISWS Sarath Indrakanti, Vijay Varadharajan, Michael Hitchens
2005	—	`conf`	Architectural Framework for Web Services Authorization. WSMDEIS Sarath Indrakanti, Vijay Varadharajan, Michael Hitchens
2005	J	`jnl`	Authorization Service for Web Services and its Application in a Health Care Domain. Int. J. Web Serv. Res. Sarath Indrakanti, Vijay Varadharajan, Michael Hitchens
2005	—	`conf`	Automated Physical Storage Provision Using a Peer-to-Peer Distributed File System. ICDE Workshops Simon Chong, Paul Andrew Watters, Michael Hitchens
2005	—	`conf`	Secure Identity Management for Pseudo-Anonymous Service Access. SPC Michael Hitchens, Judy Kay, Bob Kummerfeld, Ajay Brar
2005	—	`conf`	Trust and authorization in the grid: a recommendation model. ICPS Huu Tran, Paul A. Watters, Michael Hitchens, Vijay Varadharajan
2004	A	`conf`	Authorization Service for Web Services and its Implementation. ICWS Sarath Indrakanti, Vijay Varadharajan, Michael Hitchens
2004	—	`conf`	Securing the Ad-Hoc On-demand Distance Vector Protocol. PDCS Michael Hitchens, Rajan Shankaran, Vijay Varadharajan
2004	J	`jnl`	Security for cluster based ad hoc networks. Comput. Commun. Vijay Varadharajan, Rajan Shankaran, Michael Hitchens
2003	B	`conf`	A secure multicast support framework for Mobile IP. WCNC Rajan Shankaran, Vijay Varadharajan, Michael Hitchens
2003	C	`conf`	Role-Based Access Control and the Access Control Matrix. ICICS Gregory Saunders, Michael Hitchens, Vijay Varadharajan
2003	B	`conf`	Secure Authorisation for Web Services. DBSec Sarath Indrakanti, Vijay Varadharajan, Michael Hitchens, Rajat Kumar Todi
2002	Misc	`conf`	Policy Administration Domains. ACISP Michael Hitchens, Vijay Varadharajan, Gregory Saunders
2002	—	`conf`	Secure Multicast Support for Mobile IP with Hierarchical Registration Approach. IASTED PDCS Rajan Shankaran, Vijay Varadharajan, Michael Hitchens
2002	—	`conf`	Security Policy Management in Distributed Systems. IASTED PDCS Michael Hitchens, Vijay Varadharajan, Gregory Saunders
2001	B	`conf`	A Distributed Location Management Scheme for Mobile Hosts. ICPADS Rajan Shankaran, Vijay Varadharajan, Michael Hitchens
2001	C	`conf`	RBAC for XML Document Stores. ICICS Michael Hitchens, Vijay Varadharajan
2001	J	`jnl`	Role-Based Access Control and the Access Control Matrix. ACM SIGOPS Oper. Syst. Rev. Gregory Saunders, Michael Hitchens, Vijay Varadharajan
2001	B	`conf`	Secure Distributed Location Management Scheme for Mobile Hosts. LCN Rajan Shankaran, Vijay Varadharajan, Michael Hitchens
2001	—	`conf`	Tower: A Language for Role Based Access Control. POLICY Michael Hitchens, Vijay Varadharajan
2000	J	`jnl`	Design and specification of role based access control policies. IEE Proc. Softw. Michael Hitchens, Vijay Varadharajan
2000	Misc	`conf`	Elements of a Language for Role-Based Access Control. SEC Michael Hitchens, Vijay Varadharajan
1999	Misc	`conf`	An Analysis of Access Control Models. ACISP Gregory Saunders, Michael Hitchens, Vijay Varadharajan
1999	C	`conf`	Issues in the Design of a Language for Role Based Access Control. ICICS Michael Hitchens, Vijay Varadharajan
1999	J	`jnl`	On the design of secure ATM networks. Comput. Commun. Vijay Varadharajan, Rajan Shankaran, Michael Hitchens
1999	B	`conf`	Secure Multicast Extensions for Mobile Networks. LCN Rajan Shankaran, Vijay Varadharajan, Michael Hitchens
1997	J	`jnl`	A New Process Migration Algorithm. ACM SIGOPS Oper. Syst. Rev. Michael Richmond, Michael Hitchens
1997	Misc	`conf`	Security Issues in Asynchronous Transfer Mode. ACISP Vijay Varadharajan, Rajan Shankaran, Michael Hitchens
1997	B	`conf`	Security services and public key infrastructure for ATM networks. LCN Vijay Varadharajan, Rajan Shankaran, Michael Hitchens
1997	—	`conf`	Subtyping and Protection in Persistent Programming Languages. HICSS (1) Michael Hollins, John Rosenberg, Michael Hitchens
1997	—	`conf`	The Design of a Flexible Class Library Management System. TOOLS (24) Michael Hitchens, Andrew Firmage
1996	A	`conf`	esign Choices For Symmetric Key Based Inter-Domain Authentication Protocols In Distributed Systems. ACSAC Michael Hitchens, Vijay Varadharajan
1994	—	`conf`	A Three-level Object-Based Model. ICCL Michael Hitchens, John Rosenberg
1993	—	`conf`	Linguistic Support for Persistent Modules and Capabilities. DBPL John Rosenberg, Michael Hitchens